Service Manual2007 Captiva Diagnostic Trouble Code (DTC) P2122, P2123, P2127, P2128, or P2138

Captiva

Diagnostic Trouble Code (DTC) P2122, P2123, P2127, P2128, or P2138

DTC Descriptor

DTC P2122 : Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123 : Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2127 : Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128 : Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138 : Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit	Short to Ground	High Resistance	Open	Short to Voltage	Signal Performance
Accelerator Pedal Position (APP) Sensor 1 5-Volt Reference Circuit	P2122	P2138	P2122	P2123	-
Accelerator Pedal Position (APP) Sensor 2 5-Volt Reference Circuit	P0122, P0222, P2122	P0121, P0221, P2138	P2127	P0123, P0223, P2123	-
Accelerator Pedal Position (APP) Sensor 1 Signal	P2122	P2138	P2122	P2123	P2138
Accelerator Pedal Position (APP) Sensor 2 Signal	P2127	P2138	P2127	P2128	P2138
Accelerator Pedal Position (APP) Sensor 1 Low Reference	-	-	P2123	-	-
Accelerator Pedal Position (APP) Sensor 1 Low Reference	-	-	P2128	-	-

Circuit/System Description

The accelerator pedal assembly contains two accelerator pedal position (APP) sensors. The APP sensors are mounted in the pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the position of the accelerator pedal. The engine control module (ECM) supplies a separate 5-volt reference and low reference circuit for each of the APP sensors.

The APP sensor 1 signal voltage increases as the pedal is depressed, from approximately 1.0 volt at rest to above 4 volts when fully depressed. The APP sensor 2 signal voltage increases as the pedal is depressed, from approximately 0.5 volt at rest to more than 2 volts with the accelerator pedal fully depressed.

Conditions for Running the DTC

The ignition is ON or the engine is operating.
The ignition 1 voltage is more than 7 volts.
The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

DTC P2122

The APP sensor 1 voltage is less than 0.84 volts for more than 4 seconds.

DTC P2123

The APP sensor 1 voltage is more than 4.82 volts for more than 4 seconds.

DTC P2127

The APP sensor 2 voltage is less than 0.66 volts for more than 4 seconds.

DTC P2128

The APP sensor 2 voltage is more than 4.82 volts for more than 4 seconds.

DTC P2138

The ECM detects that the voltage difference between APP sensor 1 and 2 is more than 0.21 volts.
The ECM detects that the voltage difference between APP sensor 1 and 2 is more than 0.27 volts with a partially pressed pedal.
The ECM detects that the voltage difference between APP sensor 1 and 2 is more than 1.07 volts with a fully pressed pedal.
The ECM detects that the APP sensor 1 voltage is more then 1.17 volts when leaving the idle range, and the voltage difference between APP sensors 1 and 2 is more than 0.04 volts.
Any of the above conditions exist for less than 4 seconds.

Action Taken When the DTC Sets

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Circuit/System Verification

Ignition ON, observe the APP Sensor parameters with a scan tool. Verify both of the APP sensor voltages are between 0.4-4.5 volts.
Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.
Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.
If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

Ignition OFF, disconnect the harness connector of the accelerator pedal assembly.
Ignition OFF, test for less than 5 ohms of resistance between the appropriate low reference circuit of the APP sensor and ground.

If greater than 5 ohms, test the low reference circuit of the APP sensor for a short to voltage, or an open/high resistance. If the circuit/connections test normal, replace the ECM.

Important : The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.

Ignition ON, test for 4.8-5.2 volts between the appropriate 5-volt reference circuit of the APP sensor and ground.

If less than 4.8 volts, test the 5-volt reference circuit of the APP sensor for a short to ground or open/high resistance. If the circuit/connections test normal, replace the ECM.
If greater than 5.2 volts, test the 5-volt reference circuit of the APP sensor for a short to voltage. If the circuit/connections test normal, replace the ECM.

Using a scan tool, verify the appropriate APP sensor voltage parameter is less than 0.3 volt.

If greater than 0.3 volt, test the signal circuit of the applicable APP sensor for a short to voltage. If the circuit/connections test normal, replace the ECM.

Install a 3-amp fused jumper wire between the appropriate signal circuit and the 5-volt reference circuit of the APP sensor. Verify the APP sensor voltage parameter is greater than 4.8 volts.

If less than 4.8 volts, test the appropriate signal circuit of the APP sensor for a short to ground or an open/high resistance. If the circuit/connections test normal, replace the ECM.
If both APP sensor voltage parameters display greater than 4.8 volts test the signal circuits of the APP sensors for a shorted together condition. If the circuit/connections test normal, replace the ECM.

If all circuits/connections test normal, test or replace the accelerator pedal assembly.

Diagnostic Trouble Code (DTC) P2176

DTC Descriptor

DTC P2176 : Minimum Throttle Position Not Learned

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit/System Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control (TAC) motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2.

Conditions for Running the DTC

The engine speed is less than 40 RPM.
The vehicle speed is 0 km/h (0 mph).
The engine coolant temperature (ECT) is between 5-85°C (41-185°F).
The intake air temperature (IAT) is more than 5-60°C (41-140°F).
The accelerator pedal position (APP) sensor angleis less than 14.9 percent.
The ignition 1 voltage is more than 10 volts.
DTC P2176 runs continuously once the above conditions are met for more than 1 second.

Conditions for Setting the DTC

The ECM detects that the TP sensor 1 voltage is not between 0.2-0.9 volts during the throttle learn procedure.
The ECM detects that the TP sensor 2 voltage is not between 4.2-4.8 volts during the throttle learn procedure.
The minimum throttle position is not learned after an ECM replacement.
Any of the above conditions exist for more than 4 seconds.

Action Taken When the DTC Sets

DTC P2176 is a Type A DTC.

Conditions for Clearing the DTC

DTC P2176 is a Type A DTC.

Circuit/System Verification

Ignition ON, rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release the pedal. Repeat the procedure several times. Observe the DTC information with a scan tool. Verify that DTCs P0121, P0122, P0123, P0221, P0222, P0223, P0638, or P2101 do not set.

If any of the above DTCs set, refer to the appropriate dTC information for further diagnosis.

DTC P2176 is an informational DTC. Perform the idle learn procedure, refer to Idle Learn Procedure.

If DTC P2176 resets after performing the idle learn procedure, replace the throttle body.

If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.

Diagnostic Trouble Code (DTC) P2177, P2179, P2187, or P2189

DTC Descriptor

DTC P2177 : Fuel Trim System Lean at Cruise or Accel Bank 1

DTC P2179 : Fuel Trim System Lean at Cruise or Accel Bank 2

DTC P2187 : Fuel Trim System Lean at Idle Bank 1

DTC P2189 : Fuel Trim System Lean at Idle Bank 2

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit Description

The engine control module (ECM) controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. Fuel delivery is controlled differently during Open and Closed Loop. During Open Loop, the ECM determines fuel delivery based on sensor signals without heated oxygen sensor (HO2S) input. During Closed Loop, the HO2S inputs are added and used by the ECM to calculate short and long term fuel delivery adjustments. If the HO2S indicate a lean condition, fuel trim values will be above 0 percent. If the HO2S indicate a rich condition, fuel trim values will be below 0 percent. Short term fuel trim values change rapidly in response to the HO2S signals. Long term fuel trim makes coarse adjustments in order to maintain an air/fuel ratio of 14.7:1.

Conditions for Running the DTC

Before the ECM can report DTCs P2177, P2179, P2187, or P2189 failed, DTCs P0101, P0121, P0122, P0123, P0133, P0153, P0221, P0222, P0223, P0336, P0338, P0443, P0458, P0459, P0461, P0462, P0463, P2066, P2067, and P2068 must run and pass.
The fuel system is in closed loop.
The long term fuel trim is active.
The engine coolant temperature (ECT) is more than 60°C (140°F).
The intake air temperature (IAT) is less than 60°C (140°F).
The evaporative emission (EVAP) canister purge solenoid valve is not enabled.
The fuel level is more than 11.6 percent.
The amount of air flow into the engine is more than 7,000 grams.
DTCs P2177, P2179, P2187 and P2189 run continuously once the above conditions are met for at least 300 seconds.

Conditions for Setting the DTC

P2177 or P2179

The Total Fuel Trim Avg. is more than 23 percent for more than 4 seconds.

P2187 or P2189

The Total Fuel Trim Avg. is more than 40 percent. The LT FT Idle/Decel is more than 7 percent. The condition exists for 4 seconds.

Action Taken When the DTC Sets

DTCs P2177, P2179, P2187 and P2189 are Type E DTCs.

Conditions for Clearing the DTC

DTCs P2177, P2179, P2187 and P2189 are Type E DTCs.

Diagnostic Aids

A fuel system delivery condition causes this DTC to set. Thoroughly inspect all items that cause a lean condition. Refer to Fuel System Diagnosis.
Any un-metered air into the engine causes this DTC to set. Thoroughly inspect all areas of the engine for vacuum leaks.
A MAF sensor condition can cause this DTC without setting a MAF DTC. If there is a MAF sensor condition, the MAF sensor parameters will appear to be within range.
Inspect the PCV valve for being the correct one for this application. Inspect the air filter for being the correct one for this application. Make sure that the engine oil fill cap is in place and that it is tight. Verify that the engine oil dip stick isfully seated.

Circuit/System Verification

If there are other DTCs set besides DTC P2177, P2179, P2187, or P2189, refer to the appropriate DTC information to diagnosis the applicable DTC.
Engine at normal operating temperature, observe the Total Fuel Trim Avg. parameter with a scan tool. The Total Fuel Trim Avg. should be between -22 to +23 percent.

Circuit/System Testing

Observe the LT FT Bn 1 and Bn 2 Cruise/Accel parameters, in order to determine whether the lean condition is effecting only one bank of the engine, or is common to both banks of the engine.

If the lean condition is common to both banks, inspect for the following conditions:

A mass air flow (MAF) sensor signal that is skewed.
The air intake system after the MAF sensor for vacuum leaks.
Fuel contamination.
Splits, kinks, or improper connections at the vacuum hoses.
The fuel system is operating lean.
Vacuum leaks at the intake manifold or throttle body.
Leaking crankcase ventilation system.
The engine control module grounds for being clean, tight, and in the correct locations.
A high engine oil level condition-A high engine oil level causes oil residue to form on the mass air flow (MAF) sensor, causing a lean indication. The MAF sensor does not need tobe replaced.

If the lean condition is common to only one bank of the engine, inspect for the following conditions:

Vacuum leaks that only affect one bank of the engine-For example, the intake manifold, the injector O-rings.
Lean injectors.
Missing, restricted, or leaking exhaust components.
The heated oxygen sensor (HO2S) is installed securely and the electrical connector is not contacting the exhaust system.
An engine mechanical condition.

If all conditions test normal, refer to Diagnostic Aids.

Diagnostic Trouble Code (DTC) P2178, 2180, P2188, or P2190

DTC Descriptor

DTC P2178 :Fuel Trim System Rich at Cruise or Accel Bank 1

DTC P2180 : Fuel Trim System Rich at Cruise or Accel Bank 2

DTC P2188 : Fuel Trim System Rich at Idle Bank 1

DTC P2190 : Fuel Trim System Rich at Idle Bank 2

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit Description

The engine control module (ECM) controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. Fuel delivery is controlled differently during Open and Closed Loop. During Open Loop, the ECM determines fuel delivery based on sensor signals without heated oxygen sensor (HO2S) input. During Closed Loop, the HO2S inputs are added and used by the ECM to calculate short and long term fuel trim fuel delivery adjustments. If the HO2S indicate a lean condition, fuel trim values will be above 0 percent. If the O2S indicate a rich condition, fuel trim values will be below 0 percent. Short term fuel trim values change rapidly in response to the HO2S signals. Long term fuel trim makes coarse adjustments in order to maintain an air/fuel ratio of 14.7:1.

Conditions for Running the DTC

Before the ECM can report DTC P2178, P2180, P2188, or P2190 failed, DTCs P0101, P0121, P0122, P0123, P0133, P0153, P0221, P0222, P0223, P0336, P0338, P0443, P0458, P0459, P0461, P0462, P0463, P2066, P2067, and P2068 must run and pass.
The fuel system is in closed loop.
The long term fuel trim is active.
The engine coolant temperature (ECT) is more than 60°C (140°F).
The intake air temperature (IAT) is less than 60°C (140°F).
The evaporative emission (EVAP) canister purge solenoid valve is not enabled.
The fuel level is more than 11.6 percent.
The amount of air flow into the engine is more than 7,000 grams.
DTCs P2178, P2180, P2188, and P2190 run continuously once the above conditions are met for at least 300 seconds.

Conditions for Setting the DTC

DTC P2178 or P2180

The Total Fuel Trim Avg. is less than -22 percent. The condition exists for 4 seconds.

DTC P2188 or P2190

The Total Fuel Trim Avg. is less than -40 percent. The LT FT Idle/Decel is less than -7 percent. The condition exists for 4 seconds.

Action Taken When the DTC Sets

DTCs P2178, P2180, P2188, and P2190 are Type E DTCs.

Conditions for Clearing the DTC

DTCs P2178, P2180, P2188, and P2190 are Type E DTCs.

Circuit/System Verification

If there are other DTCs set besides the appropriate DTC information to diagnosis the applicable DTC.
Engine at normal operating temperature, observe the Total Fuel Trim Avg. parameter with a scan tool. The Total Fuel Trim Avg. should be between -22 to +23 percent.

Circuit/System Testing

Observe the LT FT Bn 1 and Bn 2 Cruise/Accel or Idle/Decel parameters, in order to determine whether the rich condition is effecting only one bank of the engine, or is common to both banks of the engine.

If the rich condition is common to both banks, inspect for the following conditions :

A mass air flow (MAF) sensor signal that is skewed.
A collapsed air intake duct
A restricted air filter element.
The MAF sensor for foreign objects.
Excessive fuel in the crankcase-Change the oil as necessary.
Fuel contamination.
The engine control module grounds for being clean, tight, and in the correct locations
An engine mechanical condition.

If the rich condition is common to only one bank of the engine, inspect for the following conditions :

Rich injectors.
Restricted exhaust system.
An engine mechanical condition.

If all conditions test normal, refer to Diagnostic Aids.

Diagnostic Trouble Code (DTC) P2195 or P2197

DTC Descriptor

DTC P2195 : HO2S Signal Biased Lean Bank 1 Sensor 1

DTC P2197 :HO2S Signal Biased Lean Bank 2 Sensor 1

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit/System Description

The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream. When the engine is started the control module operates in an Open Loop mode, ignoring the HO2S signal voltage while calculating the air/fuel ratio. The control module supplies the HO2S with a reference or bias voltage of about 450 mV. While the engine runs the HO2S heats up and begins to generate a voltage within a range of 0–1,000 mV. This voltage will fluctuate above and below the bias voltage. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module uses the HO2S voltage to determine the air/fuel ratio. An HO2S voltage that increases above bias voltage toward 1,000 mV indicates a rich fuel mixture. An HO2S voltage that decreases below bias voltage toward 0 mV indicates a lean fuel mixture.

The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster.

This allows the system to enter Closed Loop earlier and the control module to calculate the air/fuel ratio sooner.

Conditions for Running the DTC

DTC P2195 or P2197

The ignition voltage is between 10-16 volts.
The engine is operating.

Conditions for Setting the DTC

P2195 and P2197

The ECM detects that the H02S Signal voltage is low.

Action Taken When the DTC Sets

DTCs P2195 and P2197 are type E DTCs.

Conditions for Clearing the DTC

DTCs P2195 and P2197 are type E DTCs.

Circuit/System Verification

Allow the engine to reach operating temperature. Engine running, observe the affected HO2S parameter with a scan tool.

The HO2S 1 value should vary from below 200 mV to above 800 mV and respond to fuelling changes.
The HO2S 2 value should change more than 200 mV when the throttle is quickly cycled 3 times from Closed to wide open and back to Closed after running the engine at 1,500 RPM for 30 seconds.

If any HO2S heater DTCs are set, diagnose those DTCs first.
The affected HO2S may be damaged due to contamination. Prior to replacing the affected HO2S, inspect for the following sources of contamination:

Circuit/System Testing

Disconnect the affected HO2S.
Ignition ON, measure for approximately 2-40 mV from the affected HO2S low signal circuit terminal to a known ground.

If more than approximately 40 mV, test the affected HO2S low signal circuit for a short to voltage. If the circuit tests normal, replace the control module.
If less than approximately 2 mV, test the affected HO2S low signal circuit for high resistance. If the circuit tests normal, replace the control module.

Measure for approximately 450 mV from the affected HO2S high signal circuit terminal and a known ground.

If more than approximately 450 mV, test the affected HO2S high signal circuit for a short to voltage. If the circuit tests normal, replace the control module.
If less than approximately 450 mV, test the affected HO2S high signal circuit for high resistance. If the circuit tests normal, replace the control module.

Install a 3A fusible link wire between the affected HO2S high signal circuit terminal and the affected HO2S low signal circuit terminal. The affected HO2S parameter should indicate 0 mV.

If not 0 mV and all circuits and connectors test normal, replace the control module.

Install a test lamp between the affected HO2S high signal circuit terminal and battery voltage. The affected HO2S parameter should indicate approximately 1,095 mV.

If not 1,095 mV and all circuits and connectors test normal, replace the control module.

If the control module and all circuits test normal, replace the affected HO2S.

Diagnostic Trouble Code (DTC) P2196 or P2198

DTC Descriptor

DTC P2196 : HO2S Signal Biased Rich Bank 1 Sensor 1

DTC P2198 : HO2S Signal Biased Rich Bank 2 Sensor 1

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit/System Description

The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster.

This allows the system to enter Closed Loop earlier and the control module to calculate the air/fuel ratio sooner.

Conditions for Running the DTC

DTC P2196 or P2198

The ignition voltage is between 10-16 volts.
The engine is operating.

Conditions for Setting the DTC

P2196 and P2198

The ECM detects that the H02S Signal voltage is high.

Action Taken When the DTC Sets

DTCs P2196 and P2198 are type E DTCs.

Conditions for Clearing the DTC

DTCs P2196 and P2198 are type E DTCs.

Circuit/System Verification

Allow the engine to reach operating temperature. Engine running, observe the affected HO2S parameter with a scan tool.

The HO2S 1 value should vary from below 200 mV to above 800 mV and respond to fuelling changes.
The HO2S 2 value should change more than 200 mV when the throttle is quickly cycled 3 times from Closed to wide open and back to Closed after running the engine at 1,500 RPM for 30 seconds.

If any HO2S heater DTCs are set, diagnose those DTCs first.
The affected HO2S may be damaged due to contamination. Prior to replacing the affected HO2S, inspect for the following sources of contamination:

Circuit/System Testing

Disconnect the affected HO2S.
Ignition ON, measure for approximately 2-40 mV from the affected HO2S low signal circuit terminal to a known ground.

If more than approximately 40 mV, test the affected HO2S low signal circuit for a short to voltage. If the circuit tests normal, replace the control module.
If less than approximately 2 mV, test the affected HO2S low signal circuit for high resistance. If the circuit tests normal, replace the control module.

Measure for approximately 450 mV from the affected HO2S high signal circuit terminal and a known ground.

If more than approximately 450 mV, test the affected HO2S high signal circuit for a short to voltage. If the circuit tests normal, replace the control module.
If less than approximately 450 mV, test the affected HO2S high signal circuit for high resistance. If the circuit tests normal, replace the control module.

Install a 3A fusible link wire between the affected HO2S high signal circuit terminal and the affected HO2S low signal circuit terminal. The affected HO2S parameter should indicate 0 mV.

If not 0 mV and all circuits and connectors test normal, replace the control module.

Install a test lamp between the affected HO2S high signal circuit terminal and battery voltage. The affected HO2S parameter should indicate approximately 1,095 mV.

If not 1,095 mV and all circuits and connectors test normal, replace the control module.

If the control module and all circuits test normal, replace the affected HO2S.

Diagnostic Trouble Code (DTC) P2227, P2228, or P2229

DTC Descriptor

DTC P2227 : Barometric Pressure (BARO) Sensor Performance

DTC P2228 : Barometric Pressure (BARO) Sensor Circuit Low Voltage

DTC P2229 : Barometric Pressure (BARO) Sensor Circuit High Voltage

Diagnostic Fault Information

Perform the Diagnostic System Check prior to using this diagnostic procedure.

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
5-Volt Reference	P2228	P2228	P2229	-
BARO Sensor Signal	P2228	P2228	P2229	-
Low Reference	P2228 -	P2229	-	-

Circuit/System Description

The barometric pressure (BARO) sensor responds to changes in altitude and atmospheric conditions. This gives the engine control module (ECM) an indication of barometric pressure. The ECM uses this information to calculate fuel delivery. The BARO sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The ECM supplies 5 volts to the BARO sensor on a 5-volt reference circuit, and provides a ground on a low reference circuit. The BARO sensor provides a voltage signal to the ECM on a signal circuit relative to the atmospheric pressure changes. The ECM monitors the BARO sensor signal for a voltage outside of the normal range.

Conditions for Running the DTC

P2227

Before the ECM can report DTC P2227 failed, DTCs P0121, P0122, P0123, P0221, P0222, P0223, P0335, P0336, P0338, P2228, and P2229 must run and pass.
The engine is operating for more than 20 seconds.
The mass air flow is more than 11 g/s.
The difference between the calculated manifold absolute pressure (MAP) and BARO pressure is less than 1.0 kPa for more than 3 seconds.
DTC P2227 runs continuously once the above conditions are met for 2 seconds.

P2228 or P2229

The engine is operating.
The DTCs run continuously once the above conditions are met for 2 seconds.

Conditions for Setting the DTC

P2227

The ECM detects that the BARO pressure changed more than 5 kPa within 20 seconds.
The ECM detects that the BARO pressure changed more than 30 kPa since the last ignition cycle.
Either condition exists for at least 4 seconds.

P2228

The ECM detects that the BARO sensor voltage is less than 0.20 volts and the BARO pressure is less than 50 kPa.
The condition is met for more than 4 seconds.

P2229

The ECM detects that the BARO sensor voltage is more than 4.8 volts and the BARO pressure is more than 115 kPa.
The condition is met for more than 4 seconds.

Action Taken When the DTC Sets

DTCs P2227, P2228, and P2229 are Type E DTCs.

Conditions for Clearing the DTC

DTCs P2227, P2228, and P2229 are Type E DTCs.

Diagnostic Aids

If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.

Circuit/System Verification

Start the engine, observe the DTC information with a scan tool. DTCs P2227, P2228, or P2229 should not set.
If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

Ignition ON, observe the BARO sensor parameter on a scan tool while moving the related harness connectors at the barometric pressure (BARO) sensor and at the engine control module (ECM). Verify the BARO parameter does not changemore than 3 kPa.

If the BARO parameter changes more than the specified value, repair the related harness/connections.

Ignition OFF, disconnect the harness connector of the BARO sensor.

Important : The signal circuit of the BARO sensor is pulled up to a voltage through a 1 mega-ohm resistor.

Ignition ON, observe the BARO Volts parameter with a scan tool. Verify the scan tool displays 4.8-5.2 volts.

If less than 4.8 volts, test the signal circuit of the BARO sensor for a short to ground. If the circuit/connections test normal, replace the ECM.
If greater than 5.2 volts, test the signal circuit of the BARO sensor for a short to voltage. If the circuit/connections test normal, replace the ECM.

Connect a fused jumper wire between the signal circuit of the BARO sensor and the ECM housing. Observe the BARO Volts parameter with a scan tool. Verify the scan tool displays 0 volts.

If greater than 0 volts, test the signal circuit of the BARO sensor for an open/high resistance. If the circuit/connections test normal, replace the ECM.

Test for 4.8–5.2 volts between the 5-volt reference circuit of the BARO sensor and ground.

If less than 4.8 volts, test the 5-volt reference circuit of the BARO sensor for a short to ground or open/high resistance. If the circuit/connections test normal, replace the ECM.
If greater than 5.2 volts, test the 5-volt reference circuit of the BARO sensor for a short to voltage. If the circuit/connections test normal, replace the ECM.

Ignition OFF, remove the ECM/TCM fuse from the underhood electrical center.

Notice : Do NOT use a test lamp to test the continuity of the circuit. Damage to the control module may occur due to excessive current draw.

Test for less than 5 ohms of resistance between the low reference circuit of the BARO sensor and ground.

If greater than 5 ohms, test the low reference circuit of the BARO sensor for an open/high resistance. If the circuit/connections test normal, replace the ECM.

If all circuits/connections test normal, replace the BARO sensor.