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Engine Control Module Scan Tool Information - LDE or 2H0

Table 1: Engine Control Module Scan Tool Data Parameters
Table 2: Engine Control Module (ECM) Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine related parameters that are available on the scan tool. The list is arranged in alphabetical order. A given parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly.

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Note: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis. If all values are within the typical range described below, refer to Symptoms - Engine Controls for engine diagnosis.

Engine Control Module Scan Tool Data Parameters

Parameter

System State

Expected Value

Description

Operating Conditions: Engine Idling/Radiator Hose Hot/Closed Throttle/Park or Neutral/Closed Loop/Accessories Off/Brake Pedal Released

5 V Reference 1, 2, 3, or 4

Ignition ON

5 V

This parameter displays the voltage sensed on the 5 V reference circuits at the control module. The scan tool will display a higher value at higher voltage. The scan tool will display a lower value at lower voltage.

5 V Reference 1, 2, 3, or 4 Circuit Status

Ignition ON

OK

This parameter displays OK if there is no 5 V reference circuit condition. If the circuit is shorted to ground or shorted to B+, Fault is displayed.

A/C Disengage 1-8 History

A/C ON

Reason for A/C Disengagement

The parameter indicates the reason the air conditioning (A/C) compressor was disengaged. The scan tool displays None, A/C Pressure, Engine Speed, Battery Voltage, Anti Stall, RPM Unstable, WOT, Launch Performance, Coolant Hot, APP, Air Bag Deploy, or A/C Relay DTC.

A/C High Side Pressure Sensor

A/C OFF

0.75-1.5 V*

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

*Varies with temperature and relative humidity.

A/C ON

1.3-2.5 V*

A/C High Side Pressure Sensor

A/C OFF

450-650 kPa* (65-95 (PSI)*

This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

*Varies with temperature and relative humidity.

Engine Speed at 2 000 RPM

1 117-2 350 kPa* (162-341 PSI)*

A/C Off for WOT

A/C ON

No

This parameter displays whether the control module is commanding the A/C compressor clutch relay OFF for wide open throttle (WOT).

A/C Disable - A/C Pressure Out of Range

A/C ON

No

This parameter displays whether the A/C pressure is out of range for normal operation as determined by the control module.

A/C Compressor Clutch Relay Control Circuit Open Test Status

A/C ON or Off

OK/Not Run

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

A/C Compressor Clutch Relay Control Circuit Low Voltage Test Status

A/C ON or Off

OK/Not Run

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

A/C Compressor Clutch Relay Control Circuit High Voltage Test Status

A/C ON or Off

OK/Not Run

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

A/C Compressor Clutch Relay Command

A/C ON

On

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal

A/C ON

Yes

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

Accelerator Pedal Position

Accelerator pedal not actuated

0%

This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module using the signals from the APP sensors.

Accelerator pedal fully actuated

100%

Air/Fuel Equivalence Ratio Command

-

Varies

This parameter displays the ratio of air to fuel as calculated by the control module based on various sensor inputs. The scan tool will display a lower air fuel ratio when a richer air to fuel mixture is commanded. The scan tool will display a higher air fuel ratio when a leaner air to fuel mixture is commanded. In closed loop operation the air fuel ratio should normally be approximately 14.7:1.

Ambient Air Temperature

-

°C (°F)

Varies

This parameter displays the surrounding air temperature, at any given altitude.

APP Sensor 1

Accelerator pedal not actuated

0.88-1.08 V

This parameter displays the actual voltage on the accelerator pedal position (APP) Sensor 1 signal circuit as measured by the control module.

Accelerator pedal fully actuated

4.17-4.37 V

APP Sensor 2

Accelerator pedal not actuated

0.39-0.59 V

This parameter displays the actual voltage on the accelerator pedal position (APP) Sensor 2 signal circuit as measured by the control module.

Accelerator pedal fully actuated

2.02-2.22 V

APP Sensor 1 and 2

-

Agree

This parameter displays the results of a control module test that compares the signals from the APP sensors 1 and 2. The scan tool will display Agree or Disagree. Agree indicates that APP sensor 1 and APP sensor 2 voltages correspond to the same accelerator pedal position. Disagree indicates that APP sensor 1 and APP sensor 2 voltages correspond to different accelerator pedal positions.

APP Sensors

-

0%

This parameter displays the average of the APP sensors as calculated by the throttle actuator control (TAC) module. The APP average is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

APP Sensor 1 Position

Accelerator pedal not actuated

0%

This parameter displays the angle of the APP sensor 1 as calculated by the control module using the signal from the APP sensor 1. APP sensor 1 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

Accelerator pedal fully actuated

100%

APP Sensor 2 Position

Accelerator pedal not actuated

0%

This parameter displays the angle of the APP sensor 2 as calculated by the control module using the signal from the APP sensor 2. APP sensor 2 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

Accelerator pedal fully actuated

100%

BARO

-

65-104 kPa (8-16 PSI) Varies with altitude

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Brake Pedal Position Circuit Signal

Brake pedal depressed

Applied

The scan tool displays Applied, or Released. This parameter shows the position of the brake pedal position sensor through the serial data bus.

Calculated Air Flow

-

g/s Varies

This parameter displays the air flow of the engine as calculated by the control module.

Calculated Catalyst Temperature

-

°C (°F)

Varies

This parameter displays the catalyst temperature as calculated by the control module.

Calculated Engine Oil Temperature

-

°C (°F)

Varies

This parameter displays the temperature of the engine oil as calculated by the control module using various sensor inputs. The engine oil temperature calculated has a range of values indicating a low value when the oil temperature is low to a high value when the oil temperature is high.

Camshaft Position Active Counter

-

0-255 Counts

This parameter displays an incrementing counter when the control module receives a signal from the camshaft position sensors.

Camshaft Position Sensor

-

Engine Speed

This parameter displays the speed of the engine as calculated by the signal from the camshaft position sensor, shown in RPM.

Catalyst Monitor Complete This Ignition Cycle

-

Yes or No

This parameter displays the monitor completion status during the current driving/monitoring cycle.

Catalyst Monitor Enabled This Ignition Cycle

-

Yes or No

This parameter displays the monitor enable status during the current driving/monitoring cycle.

Catalyst Monitor Test Counter

-

0 Counts

This parameter displays the number of iterations of the catalyst monitor diagnostic test that have been performed since a code clear (used to determine if a sufficient number of tests have run to report a passing condition).

Catalyst Monitor Not At Idle Test Conditions Met

-

Yes or No

This parameter displays the status of the catalyst monitor diagnostic. Off Idle Conditions Met indicates if the off idle conditions for the catalyst monitor diagnostic have been met. Once the Off Idle Conditions are met the vehicle can return to idle and allow the catalyst monitor diagnostic test to run.

Catalyst Monitor Test Result

-

Varies

This parameter displays the status of the catalyst monitor diagnostic.

Catalyst Monitor Test State

-

Varies

This parameter displays when the catalyst monitor diagnostic is actively running a test. This condition will only be true when the vehicle is at idle.

Crankshaft Position Active Counter

-

0-255 Counts

This parameter displays an incrementing counter when the control module receives a signal from the crankshaft position sensor.

Crankshaft Position Resynchronisation Counter

-

0 Counts

This parameter displays the number of counts the control module resynchronises with the crankshaft position sensor.

Crankshaft Position Sensor

-

Engine Speed

This parameter displays the engine speed as calculated by the control module using the signal from the crankshaft position sensor.

Cold Start Up

-

Varies

This parameter displays whether the engine meets the conditions for a cold startup during the present ignition cycle. The scan tool displays Yes when the conditions for a cold startup are met during this ignition cycle. The scan tool displays No when the conditions for a cold startup are not met during the present ignition cycle. Conditions for a cold startup require the coolant temperature and the intake air temperature to be below a predetermined temperature and within a certain range of each other. These conditions must occur after the engine was warmed up to a specific temperature during the previous ignition cycle.

Control Module Voltage Signal

-

B+

This parameter displays the state of the ignition system voltage available at the control module.

Cooling Fan Relay 1 Control Circuit Open Test Status

-

OK or Not Run

This parameter displays the status of the fan relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cooling Fan Relay 1 Control Circuit Low Voltage Test Status

-

OK or Not Run

This parameter displays the status of the fan relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cooling Fan Relay 1 Control Circuit High Voltage Test Status

-

OK or Not Run

This parameter displays the status of the fan relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cooling Fan Relay 1 Command

-

Varies

This parameter displays the commanded state of the cooling fan relay 1 control circuit. The cooling fan relay 1 should be ON when the scan tool indicates the fan control relay 1 command is ON. The cooling fan relay 1 should be OFF when the scan tool indicates the fan control Relay 1 Command is OFF.

Cooling Fan Relay 2 Control Circuit Open Test Status

-

OK or Not Run

This parameter displays the state of the fan relay control circuit. The parameter displays Fault if the fan relay control circuit is open.

Cooling Fan Relay 2 Control Circuit Low Voltage Test Status

-

OK or Not Run

This parameter displays the status of the fan relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cooling Fan Relay 2 Control Circuit High Voltage Test Status

-

OK or Not Run

This parameter displays the status of the fan relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cooling Fan Relay 2 Command

-

Varies

This parameter displays the commanded state of the cooling fan relay 2 control circuit. The cooling fan relay 2 should be ON when the scan tool indicates the fan control Relay 2 command is ON. The cooling fan relay 2 should be OFF when the scan tool indicates the fan control Relay 2 command is OFF.

CPP Learned Apply Position

-

Volts

This parameter displays the position learned for the clutch pedal position sensor when the clutch pedal is fully applied during the associated learn procedure.

CPP Learned Release Position

-

Volts

This parameter displays the position learned for the clutch pedal position sensor when the clutch pedal is released.

CPP Sensor

-

%

This parameter displays the displacement of the clutch pedal (corrected and normalised based upon its learned released and fully applied positions), where 0% corresponds to the clutch pedal being released and 100% corresponds to the clutch pedal being fully applied.

CPP Sensor

-

Volts

This parameter displays the clutch pedal position sensor analogue input as a percentage of its reference voltage.

Crank Request Signal

Ignition switch not in the crank position

No

This parameter displays whether the ignition switch has been cycled to the crank position requesting the control module to activate the starter relay.

Ignition switch in the crank position

Yes

Cruise Control Disengage History 1-8

Cruise Control ON

Reason for Cruise Disengagement

The parameter displays the last 8 cruise control disengages in order from 1-8, with 8 being the most recent. There are approximately 40 possible causes for the cruise control to disengage.

Cruise Control Inhibit Reason

Cruise Control ON

Varies

The parameter displays the reason why the cruise control system is inhibited. There are approximately 40 possible causes for the cruise control to be inhibited.

Current Gear

Transmission in Park or Neutral

1-6

Displays Unknown, 1, 2, 3, 4, 5, or 6. This parameter indicates the current commanded gear position.

Cycles of Misfire Data

-

Incrementing 0-100 Counts

This parameter displays the number of cylinder firing events recorded by the control module.

Cylinder 1-4 Current Misfire Counter

-

0 Counts

The scan tool displays 0-255 counts. This parameter displays the number of misfires that have been detected during the last 200 cylinder firing events. The counters may normally display some activity, but the activity should be nearly equal for all of the cylinders, and in low numbers.

Cylinder 1-4 History Misfire Counter

-

0 Counts

The scan tool displays 0-255 counts. The misfire history counters display the total level of misfire that has been detected on each cylinder. The misfire history counters will not update or show any activity until a misfire DTC P0300 00 has become active. The misfire history counters will update every 200 cylinder firing events.

Cylinder 1-4 Injector Control Circuit Open Test Status

-

OK

This parameter displays the state of the injector control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cylinder 1-4 Injector Disabled - Misfire Detected

-

No

This parameter displays the status of the fuel injector driver by the control module. The scan tool will display YES if the fuel injector is being disabled due to a misfire detection. The scan tool will display NO if the fuel injector is not being disabled by the control module due to a misfire.

Cylinder 1-4 Injector Control Circuit Low Voltage Test Status

-

OK

This parameter displays the state of the injector control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cylinder 1-4 Injector Control Circuit High Voltage Test Status

-

OK

This parameter displays the state of the injector control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Cylinder 1-4 Knock Detected

-

NO

This parameter displays the status of each cylinder for knock detection by the control module. The scan tool will display YES if a knock condition has been detected related to that cylinder combustion event. The scan tool will display NO if there is no knock condition detected related to that cylinder combustion event.

Deceleration Fuel Cut-Off

-

Inactive

This parameter displays the status of the operating mode used to turn off the fuel injectors during certain deceleration conditions. When the scan tool displays Active, the control module has turned off the fuel injectors. When the scan tool displays Inactive, the fuel system is operating normally.

Desired ECT

-

°C (°F)

Varies

This parameter displays the desired engine coolant temperature in degrees.

Desired Exhaust Camshaft Position

-

3-7°

This parameter displays the desired exhaust camshaft angle as commanded by the control module. The scan tool will display a higher value for more advanced exhaust valve timing, such as high engine load or speed conditions. The scan tool will display a lower value for less advance exhaust valve timing, such as at idle.

Desired Idle Speed

-

600-950 RPM

This parameter displays the desired engine idle speed as commanded by the control module.

Desired Intake Camshaft Position

-

11-15°

This parameter displays the desired intake camshaft angle as commanded by the control module. The scan tool will display a higher value for more advanced intake valve timing, such as high engine load or speed conditions. The scan tool will display a lower value for less advance intake valve timing, such as at idle.

Desired Throttle Position

-

2-6%

This parameter displays the desired throttle position angle commanded by the control module.

Distance Since DTC Cleared

-

Varies

This parameter displays the distance accumulated since an emission diagnostic trouble code was cleared. The scan tool will display increasing distance as the vehicle is driven.

Distance Since Last Malfunction

-

Varies

This parameter displays the distance accumulated when the emission diagnostic trouble code last failed.

Engine Controls Ignition Relay Control Circuit Open Test Status

-

Not Run

This parameter displays the state of the engine control ignition relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Controls Ignition Relay Control Circuit Low Voltage Test Status

-

OK

This parameter displays the state of the engine control ignition relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Controls Ignition Relay Control Circuit High Voltage Test Status

-

Not Run

This parameter displays the state of the engine control ignition relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Controls Ignition Relay Command

-

ON

This parameter displays the commanded state of the engine control ignition relay control circuit. The scan tool will display ON or OFF. ON indicates the engine control ignition relay control circuit is being grounded by the control module, allowing voltage to other control module circuits and systems. OFF indicates the engine control ignition relay is not being commanded ON by the control module.

Engine Controls Ignition Relay Feedback Signal

-

B+

This parameter displays the voltage available at the engine control ignition relay pin of the control module.

ECT Sensor 1

-

-39 to +140°C (-38 to +284°F)

Varies

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor 1.

ECT vs. IAT Sensor Temperature at Last ECT vs. RCT Malfunction Detection

-

Agree

This parameter displays that the temperature values of the ECT sensor 1 and IAT sensors did not agree at the time of the most recent event of the ECT/RCT performance diagnostic.

Engine Coolant Thermostat Heater Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the engine coolant thermostat heater. The scan tool will display OK, Fault or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Coolant Thermostat Heater Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the engine coolant thermostat heater. The scan tool will display OK, Fault or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Coolant Thermostat Heater Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the engine coolant thermostat heater. The scan tool will display OK, Fault or Not Run. OK indicates that no circuit faults are detected during the current test.

Engine Coolant Thermostat Heater Command

-

0-100%

This parameter displays the commanded duty cycle for the engine coolant thermostat.

Engine Load

Engine Idling

11-30%

Varies

This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.

Engine speed at 2 500 RPM

25-40%

Engine Off Time

Ignition Switch in the OFF Position

Varies

This parameter displays the amount of time that has elapsed since the engine was last cycled OFF. The scan tool displays the time in hours, minutes, and seconds. The engine OFF time will reset to zero when the engine starts.

Engine Oil Level Switch

-

OK

This parameter displays if the level of the engine oil is within range as determined by the control module from information received from the engine oil level switch.

Engine Oil Pressure Switch

-

OK

This parameter displays the state of the engine oil pressure as determined by the control module. The control module monitors the engine oil pressure switch to determine if the engine oil pressure is sufficient. The scan tool displays Low when the engine oil pressure is below a predetermined value.

Engine Run Time

Engine Operating

Varies

This parameter displays the time elapsed since the engine was started. The scan tool will display the time in hours, minutes and seconds. The engine run time will reset to zero when the engine stops running.

Engine Speed

Engine Cranking

Greater than 60 RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position sensor.

Engine Idling

Approximately 650-950 RPM

EVAP Purge Solenoid Valve Control Circuit Open Test Status

-

OK

This parameter displays the status of the evaporative emission (EVAP) purge solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

EVAP Purge Solenoid Valve Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the evaporative emission (EVAP) purge solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the evaporative emission (EVAP) purge solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

EVAP Purge Solenoid Valve Command

-

10-20%

This parameter displays the on-time or duty cycle of the EVAP canister purge solenoid commanded by the control module. Zero percent indicates no purge. One hundred percent indicates full purge.

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Open Test Status

-

OK

This parameter displays the status of the exhaust camshaft actuator solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the exhaust camshaft actuator solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the exhaust camshaft actuator solenoid control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Exhaust Camshaft Position Active Counter

-

Varies in Counts

This parameter displays an incrementing counter when the control module receives a signal from the exhaust camshaft position sensor.

Exhaust Camshaft Position

-

2-8°

This parameter displays the retard position of the camshaft in degrees of camshaft rotation from the parked position. Zero indicates the camshaft is in the parked position.

Exhaust Camshaft Position Command

-

45-75%

This parameter displays the commanded duty cycle for the exhaust camshaft as commanded by the control module.

Exhaust Camshaft Position Variance

-

This parameter indicates the difference between the actual camshaft angle and the desired camshaft angle.

Extended Travel Brake Pedal Switch

Brake pedal depressed

Applied

The scan tool displays Applied, or Released. This parameter shows the position of the brake pedal position sensor through the serial data bus.

Fuel Control Loop Status

-

Closed Loop

This parameter displays the state of the fuel control system as commanded by the control module. Closed loop operation indicates that the control module is controlling the fuel delivery based off the oxygen sensors input signal. In open loop operation the control module ignores the oxygen sensor input signal and bases the amount of fuel to be delivered on other sensor inputs.

Fuel Enrichment - Hot Catalyst

-

No

This parameter displays if the control module is commanding catalyst protection.

Fuel Enrichment - Hot Coolant

-

Inactive

This parameter displays the status of the fuel delivery system. The scan tool will display Active if the fuel system is running in open loop due to a temperature condition. The scan tool will display Inactive if the fuel system is operating normally.

Fuel Level Sensor

-

Varies

This parameter displays the approximate fuel level in the fuel tank as a voltage. The control module calculates this level using the signal from the sensor used to monitor the fuel in the tank. The scan tool will display a low reading when the fuel level in the tank is near empty. The scan tool will display a high reading when the fuel level in the tank is high or near full.

Fuel Pump Relay Control Circuit Open Test Status

-

Not Run

This parameter displays the status of the fuel pump relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Fuel Pump Relay Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the fuel pump relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Fuel Pump Relay Control Circuit High Voltage Test Status

-

Not Run

This parameter displays the status of the fuel pump relay control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Fuel Pump Relay Command

Ignition ON, engine OFF

Fuel pump on for 2 s

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Engine idling

On

Fuel Tank Pressure Sensor

-

1.3-1.7 V

This parameter displays the voltage signal received by the control module from the fuel tank pressure sensor.

Fuel Tank Rated Capacity

-

70 L (18.4 Gal)

This parameter displays the rated maximum quantity of fuel the fuel tank will hold. This is calibrated in the control module to match the vehicle.

Fuel Trim Memory Cell

-

Varies

This parameter displays the fuel trim cell number as calculated by the control module based on engine speed and load inputs. The scan tool will display a lower number as conditions are closer to idle, and a higher number as conditions approach maximum engine speed and maximum load.

Fuel Trim Learn

-

Enabled

This parameter displays Enabled when conditions are appropriate for enabling long term fuel trim corrections. This indicates that the long term fuel trim is adapting continuing amounts of short term fuel trim. If the scan tool displays Disabled, then long term fuel trim will not respond to changes in short term fuel trim.

Fuel Trim System Test State

-

Monitoring

This parameter indicates the status of the Fuel Trim System Test. The scan tool will display Disabled, Enabled, Monitoring, or Run Purge Test.

Fuel Volatility

-

Varies

This parameter indicates the rate the fuel can be vaporized in the cylinder as calculated by the control module. The scan tool displays Low, Moderate, or High. The scan tool will display HIGH when the fuel volatility is high. The scan tool will display LOW when the fuel volatility is low.

Generator F-Terminal Signal

-

30-70%

This parameter indicates the generator field duty cycle as commanded by the voltage regulator or control module. The scan tool will display a higher value for a higher commanded generator output, and a lower value for a lower commanded generator output.

Generator L-Terminal Circuit Open Test Status

-

Not Run

This parameter displays the status of the Alternator L-Terminal circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Generator L-Terminal Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the Alternator L-Terminal circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Generator L-Terminal Circuit High Voltage Test Status

-

OK

This parameter displays the status of the Alternator L-Terminal circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Generator L-Terminal Signal Command

-

ON

This parameter displays the commanded state of the Alternator L-Terminal output.

HO2S 1 or HO2S 2

Ignition ON, Engine OFF

50-900 mV

This parameter indicates the heated oxygen sensor (HO2S) sensor 1 or 2, output voltage as measured by the control module. The scan tool will display a higher value during a rich condition, and a lower value during a lean condition.

Engine Operating

Varies

HO2S 1 or HO2S 2 Heater

-

0.42-0.62 A

This parameter displays the amperage of the HO2S heater commanded by the control module.

HO2S 1 or HO2S 2 Heater Command

-

ON

This parameter displays the commanded state of the HO2S 1 or HO2S 2 heater circuit by the control module. The scan tool will display ON when the heater is commanded ON. The scan tool will display OFF when the heater is commanded OFF.

HO2S 1 or HO2S 2 Heater Command

-

0-99%

This parameter displays the commanded state of the HO2S 1 or HO2S 2 heater by the control module. The scan tool will display a higher value as the heater command is increased, and a lower value if the heater is not commanded ON.

HO2S 1 or HO2S 2 Heater Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the HO2S 1 or HO2S 2. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

HO2S 1 or HO2S 2 Heater Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the HO2S 1 or HO2S 2. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

HO2S 1 or HO2S 2 Heater Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the HO2S 1 or HO2S 2. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

HO2S Heater Monitor Complete This Ignition Cycle

-

Yes or No

This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

HO2S Heater Monitor Enabled This Ignition Cycle

-

Yes or No

This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

IAT Sensor

-

-39 to +140°C (-38 to +284°F)

This parameter displays the temperature of the air entering the air induction system based on input to the control module from the intake air temperature (IAT) sensor.

Ignition 1 Signal

-

B+

This parameter displays B+ when the control module detects a voltage at the ignition 1 input terminal.

Ignition Accessory Signal

-

ON

This parameter displays the state of the ignition accessory position input to the control module from the ignition switch.

Ignition Switch Status

-

Active

This parameter displays active when the ignition switch is supplying battery voltage to the control module ignition circuit.

Ignition Timing

-

-4 to +15°

This parameter displays the amount of spark advance the control module is commanding. The control module determines the desired advance.

Ignition Coil 1-4 Control Circuit Open Test Status

-

OK

This parameter displays the state of the Ignition control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Ignition Coil 1-4 Control Circuit Low Voltage Test Status

-

OK

This parameter displays the state of the Ignition control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Ignition Coil 1-4 Control Circuit High Voltage Test Status

-

OK

This parameter displays the state of the Ignition control circuit. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Manifold Tuning Control Valve Control Circuit Command

-

Off

This parameter displays the state of the Intake Manifold Tuning Valve solenoid control circuit as commanded by the control module.

Intake Manifold Tuning Control Valve Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Manifold Tuning Valve solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Manifold Tuning Control Valve Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Manifold Tuning Valve solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Manifold Tuning Control Valve Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Manifold Tuning Valve solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Injector Duty Cycle

-

2-3 ms

This parameter displays the average pulse width of the fuel injectors as determined by the control module.

Intake Camshaft Position Actuator Solenoid Valve Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Camshaft Position solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Camshaft Position solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the Intake Camshaft Position solenoid. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Intake Camshaft Position Active Counter

-

Varies in Counts

This parameter displays an incrementing counter when the control module receives a signal from the intake camshaft position sensor.

Intake Camshaft Position

-

8-18°

This parameter displays the advance position of the camshaft in degrees of camshaft rotation from the parked position. Zero indicates the camshaft is in the parked position.

Intake Camshaft Position Command

-

45-75%

This parameter displays the commanded duty cycle for the intake camshaft as commanded by the control module.

Intake Camshaft Position Variance

-

This parameter indicates the difference between the actual camshaft angle and the desired camshaft angle.

Intake Manifold Pressure

-

32-53 kPa (4.6-7.6 PSI)

This parameter displays the pressure difference between the MAP and the barometric pressure (BARO) as calculated by the control module.

Knock Retard

-

This parameter displays the amount of spark advance the control module removes from the ignition control spark advance in response to the signal from the knock sensors.

Long Term Fuel Trim

-

-10 to +10%

The scan tool range is -99 to +99%. This parameter indicates the Long Term fuel trim correction as commanded by the ECM. A change made to the fuel delivery will be indicated by the Long and Short Term values. The Short Term values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term values change in response to the changes in the Short Term. The Long Term makes coarse adjustments to the fueling in order to recenter and restore control to the Short Term. The Short Term and the Long Term can be monitored with a scan tool. A positive fuel trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.

Long Term Fuel Trim Test Average

-

0.98%

Varies

This parameter is the average long term fuel trim for this bank as calculated by the control module. The scan tool will display a value more than 0 percent indicating that time is being added to the injector pulse width, increasing the amount of fuel to this bank of the engine. The scan tool will display a value of less than 0, indicating time is being subtracted from the injector pulse width, reducing the amount of fuel to this bank of the engine. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Long Term Fuel Trim Test Average without Purge

-

1.02%

Varies

This parameter is calculated by the control module based on the Short Term Fuel Trim value. The Long Term Fuel Trim is used for the long term correction of the fuel delivery. The scan tool will display a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

MAF Performance Test

-

OK

This parameter displays the status of the mass air flow (MAF) performance test by the control module. The scan tool will display OK if no condition is detected. The scan tool will display Fault if the control module detects a condition during the test.

MAF Sensor

Engine Idling

1.7-3.7 g/s

This parameter indicates the quantity calculated by the control module based on a signal from the MAF sensor. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.

Engine speed at 2 500 RPM

5.5-7.5 g/s

MAF Sensor

-

1 700-2 100 Hz

This parameter indicates the frequency signal received from the MAF sensor by the control module. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.

Malfunction Counter

-

Counts

This parameter displays the number of times a DTC failed.

MAP Performance Test 1

-

OK

This parameter displays the status of the MAP performance test 1 by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the test.

MAP Performance Test 2

-

OK

This parameter displays the status of the MAP performance test 2 by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the test.

MAP Sensor

Engine Idling

26-52 kPa (3.7-7.6 PSI)

This parameter displays the pressure from the MAP sensor to the control module.

MAP Sensor

Engine Idling

0.98-1.42 V

This parameter displays the signal voltage from the MAP sensor to the control module.

MIL Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the malfunction indicator lamp control (MIL). The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

MIL Control Circuit Low Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the malfunction indicator lamp control (MIL). The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

MIL Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the malfunction indicator lamp control (MIL). The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Malfunction Indicator Lamp (MIL)

-

Off

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

MIL Requested by DTC

-

NO

This parameter indicates the reason the control module illuminated the MIL. The scan tool will display YES when the MIL is requested as a result of an A or B type DTC. The scan tool will display NO if the MIL is illuminated for another reason, such as transmission DTCs.

Not Run Counter

-

Counts

This parameter displays the number of times a DTC does not run.

O2S/HO2S Monitor Complete This Ignition Cycle

-

Yes or No

This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

O2S/HO2S Monitor Enabled This Ignition Cycle

-

Yes or No

This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

Pass Counter

-

Counts

This parameter displays the number of times a DTC passed.

Power Enrichment

-

Inactive

This parameter displays the status of the operating mode of the control module used to increase fuel delivery during certain acceleration conditions.

Radiator Coolant Temperature Sensor

-

-39 to +140°C (-38 to +284°F)

This parameter displays the status of the radiator coolant temperature Sensor.

RCT vs. IAT Sensor Temperature at Last ECT vs. RCT Malfunction Detection

-

Agree

This parameter displays that the temperature values of the RCT (ECT 2) and IAT sensors did not agree at the time of the most recent event of the RCT/IAT performance diagnostic.

Reduced Engine Power

-

Inactive

This parameter displays the status of the operating mode of the control module used to reduce engine power to prevent catalyst or engine damage or due to a Throttle Actuator Control (TAC) system condition.

Reduced Engine Power History

-

OK

This parameter displays the last reason that ECM has Commanded Reduced Engine Power. The scan tool displays one of the following when Reduced Engine Power is commanded:

    • TAC DTC
    • Fan Control DTC
    • ECT Overtemperature
    • Engine Oil Overtemperature

Remaining Fuel in Tank

-

Liters (Gallons)

Varies

This parameter displays the amount of fuel remaining in the fuel tank as measured in liters (gallons). The control module determines the amount of fuel remaining in the tank by using information from the fuel level sensor. The scan tool will display a higher value with a full fuel tank, and a lower value with an empty fuel tank.

Remaining Fuel in Tank

-

0-100%

Varies

This parameter displays the amount of fuel remaining in the fuel tank as measured in percentage. The control module determines the amount of fuel remaining in the tank by using information from the fuel level sensors. The scan tool will display a higher value with a full fuel tank, and a lower value with an empty fuel tank.

Reverse Position Switch

-

OFF

Manual Transmission Reverse Switch ON indicates that the reverse switch hard wire input to the ECM is active.

Short Term Fuel Trim

-

-10 to +10%

The Short Term values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term values change in response to the changes in the Short Term. The Long Term makes coarse adjustments to the fueling in order to recenter and restore control to the Short Term. The Short Term and the Long Term can be monitored with a scan tool. A positive fuel trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.

Short Term Fuel Trim Test Average

-

-3-99%

Varies

This parameter displays the short term closed loop fuel correction. This value is compared to predetermined thresholds to determine if the fuel trim diagnostic is passing or failing.

Start Up ECT

-

-39 to +140°C (-38 to +284°F)

This parameter displays the temperature of the engine coolant on start up based on input to the control module from the ECT sensor 1.

Start Up IAT

-

-39 to +140°C (-38 to +284°F)

This parameter displays the temperature of the intake air at start in the air induction system based on input to the control module from the IAT sensor.

Starter Relay Control Circuit Open Test Status

-

OK

This parameter displays the status of the control circuit for the starter relay. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Starter Relay Control Circuit Low Voltage Test Status

-

Not Run

This parameter displays the status of the control circuit for the starter relay. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Starter Relay Control Circuit High Voltage Test Status

-

OK

This parameter displays the status of the control circuit for the starter relay. The scan tool displays OK, Fault, or Not Run. OK indicates that no circuit faults are detected during the current test.

Starter Relay Command

-

OFF

The scan tool displays ON or OFF. The scan tool displays OFF until the ignition is placed into the CRANK position.

TAC Forced Engine Shutdown

-

NO

This parameter indicates the status of TAC control by the control module. The scan tool will display YES if the engine has been shut down due to a throttle control fault. The scan tool will display NO if the engine has not been shut down by a throttle control fault.

TAC Motor

-

Disabled

This parameter indicates the status of the TAC motor driver by the ECM. The scan tool will display Enabled if TAC motor operation is allowed. The scan tool will display disabled if the TAC motor is disabled.

TAC Motor Command

-

0-100%

Varies

This parameter displays the percentage of the commanded state of the TAC motor by the control module.

Throttle Body Idle Air Flow Compensation

-

0-100%

Varies

This parameter displays the amount of airflow compensation in response to engine intake air flow restrictions. For example, throttle plate coking.

TCC/Cruise Control Brake Pedal Switch

-

Released

This parameter displays that the state of the redundant discrete brake switch input to the controller indicates that the brake is applied.

Traction Control Torque Delivered Signal

-

0-3%

Varies

This parameter displays the estimated engine torque delivered by the powertrain, as a percentage of maximum engine torque, that is provided to the Antilock Braking System/Traction Control System module via the delivered torque PWM output from the ECM.

Traction Control Torque Request Signal

-

0-30%

Varies

This parameter displays the estimated engine torque delivered by the powertrain, as a percentage of maximum engine torque, that is provided to the Antilock Braking System/Traction Control System module via the delivered torque PWM output from the ECM.

Torque Delivered Signal

-

1.1-6.8 N·m

This parameter displays the torque delivered from the engine to the transmission as calculated by the control module. The scan tool will display a higher value for higher torque, and a lower value for lower torque.

Torque Management Ignition Timing Retard

-

15-25°

This parameter displays how much the ignition spark timing is being retarded to control torque by the control module. The scan tool will display a higher value under extreme torque control conditions such as spinning wheels. The scan tool will display a lower value under low torque control conditions such as light driving.

Total Knock Retard

-

This parameter displays how much ignition spark timing is being retarded due to all control systems monitored by the control module. The scan tool will display a high value during extreme conditions such as high temperatures and antilock braking. The scan tool will display a lower value during lighter driving conditions.

Total Misfire

-

0 Counts

This parameter displays the total number of cylinder firing events that the control module detected as misfires for the last 200 crankshaft revolution sample period.

Throttle Position

-

2-6%

This parameter displays the actual throttle position angle indicated by the control module using information from the two Throttle Body sensors.

Throttle Position Performance Test

-

OK

This parameter displays the status of the throttle position performance test by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the test.

Throttle Position Sensor 1

Accelerator pedal not actuated

4.14-4.34 V

This parameter displays the voltage signal sent to the control module from throttle position sensor 1 of the throttle assembly. The throttle position sensor 1 is a range of values indicating a high voltage when the throttle is closed to a low voltage when the throttle plate is fully open.

Accelerator pedal fully actuated

3.50-3.37 V

Throttle Position Sensor 1 Position

-

2-6%

This parameter displays the angle of the throttle position sensor 1 as calculated by the control module using the signal from the throttle position sensor 1. The throttle position sensor 1 is a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is fully open.

Throttle Position Sensor 1 Learned Minimum

-

0.5-0.71 V

This parameter displays the learned minimum voltage for throttle position sensor 1 as determined by the control module this ignition cycle.

Throttle Position Sensor 2

Accelerator pedal not actuated

0.68-0.88 V

This parameter displays the voltage signal sent to the control module from throttle position sensor 2 of the throttle assembly. The throttle position sensor 2 is a range of values indicating a low voltage when the throttle is closed to a high voltage when the throttle plate is fully open.

Accelerator pedal fully actuated

1.35-1.55 V

Throttle Position Sensor 2 Position

-

2-6%

This parameter displays the angle of the throttle position sensor 2 as calculated by the control module using the signal from the throttle position sensor 2. The throttle position sensor 2 is a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is fully open.

Throttle Position Sensor 2 Learned Minimum

-

0.55-0.75 V

This parameter displays the learned minimum voltage for throttle position sensor 2 as determined by the control module this ignition cycle.

Throttle Position Sensors 1 and 2

-

Agree

This parameter displays the results of a control module test that compares the signals from the Throttle Body sensors 1 and 2. The scan tool will display Agree or Disagree. Agree indicates that throttle position sensor 1 and throttle position sensor 2 voltages correspond to the same throttle position. Disagree indicates that throttle position sensor 1 and throttle position sensor 2 voltages correspond to different throttle positions.

Traction Control Status

-

Inactive

This parameter displays Active if the electronic brake and traction control module is commanding traction control.

Vehicle Speed Sensor

-

0 km/h (0 MPH)

This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).

Warm-ups Since DTC Cleared

-

Varies

This parameter displays the number of warm-ups since the DTC was cleared in counts.

Warm-ups without Emission Malfunctions

-

Varies

This parameter displays the number of warm up cycles that have occurred without an emission fault present. The scan tool will display a 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without an emission fault.

Warm-ups without non emission Malfunctions

-

Varies

This parameter displays the number of warm up cycles that have occurred without a non emission fault present. The scan tool will display a 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without a non emission fault.

Wide Open Throttle

-

NO

This parameter displays the throttle status commanded by the control module. The scan tool will display YES is the vehicle throttle is commanded to wide open. The scan tool will display NO if the vehicle throttle is commanded to an amount less than 100%.

Engine Control Module (ECM) Scan Tool Output Controls

Output Control

Description

A/C Compressor Clutch Relay

This function activates the A/C compressor relay. The normal commanded state of the A/C relay is None. The A/C compressor will turn ON or OFF when commanded ON or OFF. The system remains in the commanded state until cancelled by the scan tool. The scan tool initiates the test when the following conditions are met:

    • In the correct power mode
    • A/C high side pressure is in range
    • Engine speed is in range
    • Ignition voltage is in range.
    • There are no A/C pressure sensor DTCs set.

Clutch Pedal Position Learn

This device control is used to trigger the procedure to learn the clutch pedal fully applied position.

Cooling Fan Relay 1

This function controls the cooling fan relay 1. The normal commanded state of the fan relay is None. The scan tool initiates the test when the following conditions are met:

    • Engine coolant temperature is not out of range
    • In the correct power mode.

Cooling Fan Relay 2

This function controls the cooling fan relay 2. The normal commanded state of the fan relay is OFF. The scan tool initiates the test when the following conditions are met:

    • Engine coolant temperature is not out of range.
    • In the correct power mode.

Crankshaft Position Variation Learn

This device control is used to activate the crankshaft position variation learn algorithm which calculates the reference pulse correction factors for the misfire diagnostic.

Cylinder Power Balance

This function disables the selected fuel injector. The normal commanded state is None. The scan tool initiates the test when the following conditions are met:

    • The engine is operating and the engine idle is stable.
    • The vehicle speed is 0 km/h (0 mph).
    • There are no vehicle speed sensor DTCs set.

If the fuel injector is disabled after 30 s, fuel injector control is not allowed again on the same fuel injector for 60 s.

Engine Controls Ignition Relay

This function controls the engine control ignition relay or main relay. The normal commanded state is None. When commanded ON or OFF, the engine control module (ECM) turns the relay ON or OFF. The system remains in the commanded state until cancelled by the scan tool. The scan tool initiates the test when the following conditions are met:

    • The ignition is ON with the engine OFF.
    • There are no crankshaft position or VSS sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).
    • In the correct power mode.

Engine Coolant Thermostat Heater

This function controls the engine coolant thermostat heater. The normal commanded state is None. The system will increase or decrease the amount of thermostat opening by changing the duty cycle in 10% increments within a range of 0-100%.

Engine Oil Life Reset

This function is used to reset the engine oil life. The engine oil remaining life is determined from engine revolutions and the distance driven since the last oil change.

Engine Speed

This function controls the idle speed override in 25 RPM, 100 RPM, and 500 RPM increments, from the base idle speed to 1 950 RPM. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph).
    • There are no VSS sensor DTCs set.

EVAP Purge Solenoid Valve

This function controls the EVAP purge solenoid valve. The normal commanded state is None. The system will increase or decrease the amount of purge by changing the duty cycle of the purge valve in 10% increments within a range of 0-100%. The scan tool initiates the test when the following conditions are met:

    • The vacuum level in the EVAP purge system is within range.
    • There are no EVAP DTCs set.
    • The EVAP system test is not in progress.
    • In the correct Power Mode.

Exhaust Camshaft Position Actuator

This function controls the selected camshaft actuator solenoid. The normal commanded state is None. The system will increase or decrease the angle of the selected camshaft in 5° increments. The scan tool initiates the test when the following conditions are met:

    • The engine is operating.
    • The commanded camshaft position is not out of range.
    • There are no crankshaft position or camshaft position sensor DTCs set.
    • Engine oil temperature is not out of range.
    • In the correct power mode.

If the actuator is disabled after 30 seconds, the actuator control is not allowed again on the same actuator for 60 seconds.

Fuel Injector Balance

This function enables the fuel injector in order to verify proper fuel injector flow. The ECM will pulse the selected injector when the following conditions are met:

    • All instruction on the scan tool completed.
    • Fuel injector selected.
    • Key ON, engine OFF.

The selected fuel injector can only be flowed or pulsed once per ignition cycle.

Fuel Pump Relay

This function controls the fuel pump relay. The normal commanded state is None. When commanded ON or OFF, the ECM turns the fuel pump ON or OFF. The scan tool initiates the test when the following conditions are met:

    • The engine speed is 0 RPM.
    • In the correct power mode.
    • The output control timer has not expired.
    • The ignition voltage is within range.

Fuel Trim Enable

This function enables or disables the ECM fuel trim learning. The normal commanded state is None.

Fuel Trim Reset

This function is used to reset the learned fuel trim values to their initial values.

Fuel Control Loop Status

This device control is used to enable or disable closed loop fuel control.

Generator L-Terminal

This function is used to override the state of the Alternator L-Terminal output. The commanded states are ON and OFF. Selecting OFF commands the ECM to turn OFF the generator and stop generating an output voltage. The scan tool initiates the test when the following conditions are met:

    • The engine is operating to turn OFF the component.
    • The vehicle speed is 0 km/h (0 mph).
    • In the correct power mode.
    • The output control timer has not expired.

HO2S Heater Learn

This function is used to trigger the reset of the learned resistances for the oxygen sensor heaters following a replacement. The learned resistances are reset to a calibration used to prevent overheating of the sensors until more accurate resistances may be learned following an extended engine OFF time.

HO2S Heater Sensor 1 or 2

This function controls the selected HO2S heater. The normal commanded state is None, On, and Off. Commanding the HO2S heater ON turns on the heater driver. The scan tool initiates the test when the following conditions are met:

    • The engine is operating.
    • The exhaust temperature is within range.
    • In the correct power mode.
    • The HO2S heaters are not over temperature.
    • The ignition voltage is not out of range while commanding the heaters ON.

Idle Learn

This function is used to reset the learned airflow adaptive values to the initial values. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph).
    •  In the correct power mode.
    • There are no throttle actuator control system DTCs set.

Ignition Timing Retard

This function is used to control the amount of spark retard. The normal commanded state is None. The system will increase or decrease the amount of spark retard by 1° increments within a range of 0-10° maximum retard. The system remains in the commanded state until cancelled by the tool.

Intake Manifold Tuning Control Valve

This device control is used to override the state of the intake manifold tuning valve output. A output test is used to select whether commanding the intake manifold tuning valve output on or off results in the valve being commanded closed or open.

Inlet Camshaft Position Actuator

This function controls the selected camshaft actuator solenoid. The normal commanded state is None. The system will increase or decrease the angle of the selected camshaft in 5° increments. The scan tool initiates the test when the following conditions are met:

    • The engine is operating.
    • The commanded camshaft position is not out of range.
    • There are no crankshaft position or camshaft position sensor DTCs set.
    • Engine oil temperature is not out of range.
    • In the correct power mode.

If the actuator is disabled after 30 seconds, the actuator control is not allowed again on the same actuator for 60 seconds.

Malfunction Indicator Lamp (MIL)

This function controls the malfunction indicator lamp (MIL). The normal commanded state is None. When commanded ON or OFF, the ECM turns the malfunction indicator lamp (MIL) ON or OFF. This output can also be monitored on the scan tool data parameter MIL Command. The system remains in the commanded state until cancelled by the scan tool.

Misfire Graphic

This function is used to graph the accumulated misfires occurring in each cylinder. The scan tool allows for a reset of the misfire graph.

Starter Relay

This function is used to override the state of the Starter Relay output. Fuel and spark are disabled to prevent the engine from starting if the starter relay output is commanded ON. The scan tool initiates the test when the following conditions are met:

    • The engine speed is 0 RPM.
    • There are no crankshaft position sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph)
    • There are no VSS sensor DTCs set.
    • There are no theft deterrent DTCs set.
    • There are no TAC system DTCs set.
    • The ignition voltage is within range.
    • In the correct power mode.
    • Not enough time has elapsed since the last time the starter has been enabled with a scan tool.

Throttle Position

This function controls the throttle valve in 10% increments. The scan tool initiates the test when the following conditions are met:

    • The engine speed is 0 RPM.
    • The vehicle speed is 0 km/h (0 mph).

The system remains in the commanded state until cancelled by the scan tool.

   


© Copyright Chevrolet. All rights reserved
   


© Copyright Chevrolet. All rights reserved