DTC P02630 : Fuel Pump Relay Control Circuit

When the ignition switch is turned ON, the ECM will activate the fuel pump relay and run the in-tank fuel pump.

The fuel pump will operate as long as the engine is cranking or running and the ECM is receiving ignition reference pulses.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.

Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.

DTC P0261 : Injector 1 Control Circuit Low Voltage

DTC P0262 : Injector 1 Control Circuit High Voltage

DTC P0264 : Injector 2 Control Circuit Low Voltage

DTC P0265 : Injector 2 Control Circuit High Voltage

DTC P0267 : Injector 3 Control Circuit Low Voltage

DTC P0268 : Injector 3 Control Circuit High Voltage

DTC P0270 : Injector 4 Control Circuit Low Voltage

DTC P0271 : Injector 4 Control Circuit High Voltage

The engine control module (ECM) enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied to the fuel injectors. The ECM controls each fuel injector by grounding the control circuit via a solid state device called a driver. The ECM monitors the status of each driver.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

An injector driver circuit that is open or shorted to voltage will causes a DTC P0261 to set. It will also cause a misfire due to an inoperative injector. A misfire DTC should also be set indicating which injector is inoperative.

Long–term and short–term fuel trims that are excessively high or low are a good indication of an injector malfunctioning. Refer to ”Fuel Injector Balance Test” in this section to check for malfunctioning injectors.

DTC P0300 : Engine Misfire Detected

DTC P0301 : Cylinder 1 Misfire Detected

DTC P0302 : Cylinder 2 Misfire Detected

DTC P0303 : Cylinder 3 Misfire Detected

DTC P0304 : Cylinder 4 Misfire Detected

The engine control module (ECM) uses information from the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM is able to detect individual misfire events. A misfire rate that is high enough can cause 3-way catalytic converter damage. The malfunction indicator lamp (MIL) will flash ON and OFF when the conditions for catalytic converter damage are present.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect for the following possible sources:

DTC P0315 : Crankshaft Position (CKP) System Variation Not Learned

The crankshaft position (CKP) system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the crankshaft position sensors. The calculated error allows the engine control module (ECM) to accurately compensate for reference period variations. This enhances the ability of the ECM to detect misfire events over a wider range of engine speed and load.

The CKP system variation compensating values are stored in ECM memory after a learn procedure has been performed. If the CKP system variation values are not stored in the ECM memory, DTC P0315 sets.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0317 : Rough Road Sensing System Input Not Present

DTC P1396 : Rough Road Sensor Performance - Variation

DTC P1397 : Rough Road Sensor Performance – No Signal

The engine control module (ECM) determines engine misfire by detecting variations in crankshaft speed. Crankshaft speed variations can also occur when a vehicle is operating over a rough road. The wheel speed sensor produces an alternating current (AC) voltage that increases with wheel speed. The ECM receives a rough road signal from the ABS module, if equipped with the anti-lock brake system (ABS). The ABS can determine if the vehicle is on a rough road surface based on the signal from each wheel speed sensor. On vehicles with Non-ABS, a rough road signal is sent from a wheel speed sensor located at the front left wheel to the ECM. The ECM can determine if the changes in crankshaft speed are due to engine misfire or are driveline induced based on the rough road signal from the wheel speed sensor. When the ECM detects a rough road condition, misfire diagnostics will be disabled.

or,

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0317 : Rough Road Sensing System Input Not Present

DTC P1396 : Rough Road Sensor Performance - Variation

DTC P1397 : Rough Road Sensor Performance – No Signal

The engine control module (ECM) determines engine misfire by detecting variations in crankshaft speed. Crankshaft speed variations can also occur when a vehicle is operating over a rough road. The wheel speed sensor produces an alternating current (AC) voltage that increases with wheel speed. The ECM receives a rough road signal from the ABS module, if equipped with the anti-lock brake system (ABS). The ABS can determine if the vehicle is on a rough road surface based on the signal from each wheel speed sensor. On vehicles with Non-ABS, a rough road signal is sent from a wheel speed sensor located at the front left wheel to the ECM. The ECM can determine if the changes in crankshaft speed are due to engine misfire or are driveline induced based on the rough road signal from the wheel speed sensor. When the ECM detects a rough road condition, misfire diagnostics will be disabled.

or,

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0324 : Knock Sensor (KS) Module Performance

The knock sensor (KS) enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the KS signal. The ECM receives the KS signal through a signal circuit. The ECM supplies a ground circuit to the KS through a low reference circuit. The ECM also supplies a shielded ground circuit to the KS. The ECM learns a KS noise level at idle and uses calibrated values for the rest of the engine speed range. The ECM should monitor a normal KS signal within the noise channel.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0325 : Knock Sensor (KS) Circuit

The knock sensor (KS) enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the KS signal. The ECM receives the KS signal through a signal circuit. The ECM supplies a ground circuit to the KS through a low reference circuit. The ECM also supplies a shielded ground circuit to the KS. The ECM learns a KS noise level at idle and uses calibrated values for the rest of the engine speed range. The ECM should monitor a normal KS signal within the noise channel.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0335 : Crankshaft Position (CKP) Sensor Circuit

DTC P0336 : Crankshaft Position (CKP) Sensor Performance

The crankshaft position (CKP) sensor circuits consist of an engine control module (ECM) supplied 5-volt reference circuit, low reference circuit and an output signal circuit. The CKP sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 58-tooth reluctor wheel on the crankshaft. Each tooth on the reluctor wheel is spaced at 60-tooth spacing, with 2 missing teeth for the reference gap. The CKP sensor produces an ON/OFF DC voltage of varying frequency, with 58 output pulses per crankshaft revolution. The frequency of the CKP sensor output depends on the velocity of the crankshaft. The CKP sensor sends a digital signal, which represents an image of the crankshaft reluctor wheel, to the ECM as each tooth on the wheel rotates past the CKP sensor. The ECM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft reluctor wheel reference gap to identify crankshaft position. This information is then used to sequence the ignition timing and fuel injection events for the engine. The ECM also uses CKP sensor output information to determine the crankshaft relative position to the camshaft, to detect cylinder misfire, and to control the CMP actuator if equipped.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0340 : Intake Camshaft Position (CMP) Sensor Circuit

DTC P0341 : Intake Camshaft Position (CMP) Sensor Performance

DTC P0366 : Exhaust Camshaft Position (CMP) Sensor Performance

The hall effect camshaft position (CMP) sensor produces a pulse for each revolution of the camshaft. The CMP output is pulse width encoded. The engine control module (ECM) uses the CMP and crankshaft position (CKP) output pulses to determine the engine speed and position. The CMP is connected to the battery voltage and to the ECM by the following circuits:

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

DTC P0351 : Ignition Coil 1 Control Circuit

DTC P0352 : Ignition Coil 2 Control Circuit

DTC P0353 : Ignition Coil 3 Control Circuit

DTC P0354 : Ignition Coil 4 Control Circuit

The engine control module (ECM) provides a ground for the electronic spark timing circuit. When the ECM removes the ground path of the ignition primary coil, the magnetic field produced by the coil collapses. The collapsing magnetic field produces a voltage in the secondary coil which fires the spark plug. The circuit between the ECM and the electronic ignition system is monitored for an open circuit, short to voltage, and low voltage. When the ECM detects a problem in the spark timing circuit, it will set a DTC.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Check and correct any abnormal engine noise before using the diagnostic table.

Any circuitry that is suspected as causing engine noise complaint should be thoroughly checked for the following conditions :

DTC P0420 : Catalyst System Low Efficiency

A 3-way catalytic converter (TWC) controls emissions of hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx). The catalyst within the converter promotes a chemical reaction, which oxidizes the HC and the CO that are present in the exhaust gas. This process converts the HC and the CO into water vapor and carbon dioxide (CO2), and reduces the NOx, converting the NOx into nitrogen. The catalytic converter also stores oxygen. The engine control module (ECM) monitors this process by using a heated oxygen sensor (HO2S) that is in the exhaust stream after the TWC. The HO2S 2 produces an output signal that the ECM uses to calculate the oxygen storage capacity of the catalyst. This indicates the ability of the catalyst to convert the exhaust emissions efficiently. The ECM monitors the efficiency of the catalyst by allowing the catalyst to heat, then wait for a stabilization period while the engine is idling. The ECM then adds and removes fuel while monitoring the HO2S 2. When the catalyst is functioning properly, the HO2S 2 response to the extra fuel is slow compared to the response of the HO2S 1, which is located before the TWC. When the HO2S 2 response is near that of the HO2S 1, the oxygen storage capability and efficiency of the catalyst may be degraded below an acceptable threshold.

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Refer to “Diagnostic Trouble Code (DTC) Type Definitions”

Inspect for the following conditions, which may cause a catalytic converter to degrade: