Engine Controls - 6.6l (DTC p0238 to p0652) Chevrolet Cab & Chassis Silverado 3500

Circuit Description

The boost pressure sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by turbocharger output, engine speed, accelerator pedal input, air temperature, and barometric pressure (BARO). A diaphragm within the boost pressure sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The boost pressure sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The boost pressure sensor provides a signal voltage to the ECM, relative to the pressure changes, on the boost pressure sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation the lowest pressure that can exist in the intake manifold is equal to the BARO. This occurs when the vehicle is operated at idle or when the ignition is ON while the engine is OFF. Under these conditions, the ECM uses the boost pressure sensor to aid in the diagnosis of the BARO sensor. The highest manifold pressure occur when the turbo charger output is high. Manifold pressure can range from 58 kPa (8 psi) when pressure are low, to more than 240 kPa (34 psi) when pressure are high, depending on the BARO. The boost pressure sensor has a range of 33-255 kPa (4-36 psi). The ECM also uses the boost pressure sensor to provide engine overboost protection.

The ECM monitors the boost pressure sensor signal for pressure outside of the normal range. If the ECM detects a boost pressure that is excessively high, DTC P0238 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC

DTC P0238 Turbo Charger Boost Sensor Circuit High Voltage

Conditions for Running the DTC

1. The engine is running.
2. DTC P0238 runs continuously within the enabling conditions.

Conditions for Setting the DTC

The ECM detects that the boost pressure is more than 254 kPa (36 psi) for 2 seconds.

Action Taken When the DTC Sets

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 4: A short to voltage on the 5-volt reference circuit will cause DTC P0653 to set.
2. 7: This step tests the signal circuit of the boost pressure sensor for a short to voltage. The short may backfeed through the sensor to the 5-volt reference circuit causing DTC P0653 to set.

DTC P0238

The boost pressure sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by turbocharger output, engine speed, accelerator pedal input, air temperature, and barometric pressure (BARO). A diaphragm within the boost pressure sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The boost pressure sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The boost pressure sensor provides a signal voltage to the ECM, relative to pressure, on the boost pressure sensor signal circuit. The ECM converts the signal voltage input to a pressure value. Under normal operation the lowest pressure that can exist in the intake manifold is equal to the BARO. This occurs when the vehicle is operated at idle, or when the ignition is ON while the engine is OFF. Under these conditions, the ECM uses the boost pressure sensor to aid in diagnosis of the BARO sensor. The highest manifold pressures occur when the turbocharger output is high. Manifold pressure can range from 58 kPa (8 psi) when pressures are low to more than 240 kPa (34 psi) when pressures are high, depending on the BARO. The boost pressure sensor has a range of 33 kPa (4 psi) to 255 kPa (36 psi). The ECM also uses the boost pressure sensor to provide engine overboost protection. The ECM calculates a predicted value for the boost pressure sensor. The ECM then compares the predicted value to the sensor input. If the ECM detects that the boost pressure sensor input is below the predicted range, this DTC will set.

This diagnostic procedure supports the following DTC

DTC P0299 Turbocharger Engine Underboost

1. DTCs P0237, P2227, P2228, P2229 are not set.
2. The engine speed is between 500-3,600 RPM.
3. The engine speed does not vary more than 50 RPM.
4. The engine run time is more than 10 seconds.
5. DTC P0299 runs continuously within the enabling conditions.

1. The ECM detects that the boost pressure input is 35 kPa below the calibrated value.
2. To obtain the desired boost, the ECM must command the turbocharger vanes closed further than expected.
3. One of the above conditions exist for more than 12 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0299

The engine control module (ECM) adjusts the fuel delivery to each cylinder in order to minimize crankshaft speed changes. If the ECM identifies a cylinder or cylinders requiring an excessive amount of fuel in order to maintain the correct crankshaft speed, DTC P0300 will set.

This diagnostic procedure supports the following DTC

DTC P0300 Engine Misfire Detected

1. The engine is running at idle for more than 30 seconds.
2. The engine coolant temperature (ECT) is more than 56°C (132°F).
3. DTC P0300 runs once per ignition cycle when the above conditions are met.
4. DTCs P0301-P0308 must run before P0300 runs.

The fuel rate adjustment for more than one cylinder exceeds an acceptable value for more than 30 seconds.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. A current DTC Last Test Failed clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Use a scan tool in order to clear the DTC.

Diagnostic Aids

A misfire with no other DTCs will be caused by an engine mechanical or fuel injector problem.

DTC P0300 (Federal Emissions)

The engine control module (ECM) adjusts the fuel delivery to each cylinder in order to minimize crankshaft speed changes. If the ECM identifies a cylinder or cylinders requiring an excessive amount of fuel in order to maintain the correct crankshaft speed, DTC P0300 will set.

This diagnostic procedure supports the following DTC

DTC P0300 Engine Misfire Detected

1. The engine is running at idle for more than 10 seconds.
2. The engine coolant temperature (ECT) is more than 56°C (132°F).
3. DTC P0300 runs twice per ignition cycle when the above conditions are met.
4. DTCs P0301-P0308 must run before DTC P0300 runs.

The fuel rate adjustment for more than one cylinder exceeds an acceptable value for more than 30 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

A misfire with no other DTCs will be caused by an engine mechanical or fuel injector problem.

DTC P0300 (California Emissions)

The engine control module (ECM) monitors changes in crankshaft speed using inputs from the crankshaft position (CKP) sensor and the fuel injection control module (FICM). The ECM adjusts the fuel delivery to each cylinder in order to minimize crankshaft speed changes. This DTC will set when the ECM identifies a cylinder or cylinders requiring an excessive amount of fuel in order to maintain the correct crankshaft speed.

DTC Descriptors

This diagnostic procedure supports the following DTCs

1. DTC P0301 Cylinder 1 Misfire Detected
2. DTC P0302 Cylinder 2 Misfire Detected
3. DTC P0303 Cylinder 3 Misfire Detected
4. DTC P0304 Cylinder 4 Misfire Detected
5. DTC P0305 Cylinder 5 Misfire Detected
6. DTC P0306 Cylinder 6 Misfire Detected
7. DTC P0307 Cylinder 7 Misfire Detected
8. DTC P0308 Cylinder 8 Misfire Detected

1. DTCs P0116, P0117, P0118, P0335, and P0336 are not set.
2. The engine is running at idle for more than 30 seconds.
3. The engine coolant temperature (ECT) is more than 56°C (132°F).
4. DTC P0301-P0308 will run once per ignition cycle once the above conditions are met.

The fuel rate adjustment for a cylinder exceeds an acceptable value for more than 30 seconds.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. A current DTC Last Test Failed clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Use a scan tool in order to clear the DTC.

A misfire with no other DTCs will be caused by an engine mechanical or fuel injector problem.

DTC P0301-P0308 (Federal Emissions)

The engine control module (ECM) monitors changes in crankshaft speed using inputs from the crankshaft position (CKP) sensor and the fuel injection control module (FICM). The ECM adjusts the fuel delivery to each cylinder in order to minimize crankshaft speed changes. This DTC will set when the ECM identifies a cylinder or cylinders requiring an excessive amount of fuel in order to maintain the correct crankshaft speed.

This diagnostic procedure supports the following DTCs

1. DTC P0301 Cylinder 1 Misfire Detected
2. DTC P0302 Cylinder 2 Misfire Detected
3. DTC P0303 Cylinder 3 Misfire Detected
4. DTC P0304 Cylinder 4 Misfire Detected
5. DTC P0305 Cylinder 5 Misfire Detected
6. DTC P0306 Cylinder 6 Misfire Detected
7. DTC P0307 Cylinder 7 Misfire Detected
8. DTC P0308 Cylinder 8 Misfire Detected

1. DTCs P0116, P0117, P0118, P0335, and P0336 are not set.
2. The engine is running at idle for more than 10 seconds.
3. The engine coolant temperature (ECT) is more than 56°C (132°F).
4. DTC P0301-P0308 will run a maximum of 3 tests per ignition cycle once the above conditions are met.

The fuel rate adjustment for a cylinder exceeds an acceptable value for more than 30 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

A misfire with no other DTCs will be caused by an engine mechanical or fuel injector problem.

DTC P0301-P0308 (California Emissions)

The hall effect crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. There are 57 teeth on the front of the crankshaft sprocket, plus a sync gap. The CKP sensor will output an ON-OFF pulse as each window passes the sensing element. The CKP sensor is connected directly to the engine control module (ECM) by the following circuits

1. The 12-volt reference circuit
2. The low reference circuit
3. The CKP sensor signal circuit

This diagnostic procedure supports the following DTC

DTC P0335 Crankshaft Position (CKP) Sensor Circuit

1. The engine is cranking or running.
2. The camshaft position (CMP) sensor signal is present.
3. DTC P0335 runs continuously when the above conditions are met.

The ECM determines no signal from the CKP sensor for less than 8 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0335

The hall effect crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. There are 57 teeth on the front of the crankshaft sprocket, plus a sync gap. The CKP sensor will output an ON-OFF pulse as each window passes the sensing element. The CKP sensor is connected directly to the engine control module (ECM) by the following circuits

1. The 12-volt reference circuit
2. The low reference circuit
3. The CKP sensor signal circuit

This diagnostic procedure supports the following DTC

DTC P0336 Crankshaft Position (CKP) Sensor Performance

1. The engine is cranking or running.
2. DTC P0336 runs continuously when the above condition is met.

The ECM determines that the CKP sensor signal is out of range for less than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. An intermittent CKP sensor signal may cause DTC P0336 to set. Wiggle the wiring harness with the engine running and observe the CKP Signal Missed parameter of the scan tool. If the parameter indicates anything other than 0, there is an intermittent condition. Refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) and «Inducing Intermittent Fault Conditions»(ref-197325-S26763912192005101100000) in Wiring Systems.
2. If the condition is intermittent, refer to «Intermittent Conditions»(/chevrolet/cab-chassis-silverado-3500/2004-2007/remont/testing-diagnostics/#engine-controls-66l-troubleshooting-diagnosis__intermittent-conditions) .

DTC P0336

The hall effect camshaft position (CMP) sensor produces 3 ON-OFF pulses 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 directly to the ECM by the following circuits

1. 5-volt reference
2. Low reference
3. CMP sensor signal

If the ECM does not see a CMP signal for more than 2 seconds, DTC P0340 will set.

This diagnostic procedure supports the following DTC

DTC P0340 Camshaft Position (CMP) Sensor Circuit

1. The ignition is ON.
2. The engine is turning faster than 60 RPM.
3. DTC P0340 runs continuously when the above conditions are met.

The ECM does not see a CMP sensor signal for more than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. An intermittent CMP sensor signal may cause DTC P0340 to set. Wiggle the wiring harness with the engine running and observe the Cam Signal Missed parameter of the scan tool. If the parameter indicates anything other than 0, there is an intermittent condition. Refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) and «Inducing Intermittent Fault Conditions»(ref-197325-S26763912192005101100000) in Wiring Systems.
2. If the CMP sensor signal is lost while running, the engine will operate normally. If the CMP sensor signal is not present on start-up, the engine will not start.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: If the engine starts and runs, the condition is suspected to be intermittent. If there is a condition with the CMP sensor circuit, the vehicle will not run.
2. 16: Inspect the CMP sensor for physical damage. The camshaft may damage the sensor.

DTC P0340

The hall effect camshaft position (CMP) sensor produces 3 ON-OFF pulses 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 directly to the ECM by the following circuits

1. 5-volt reference
2. Low reference
3. CMP sensor signal

If the ECM determines that the CMP sensor signal is out of range for less than 2 seconds, DTC P0341 will set.

This diagnostic procedure supports the following DTC

DTC P0341 Camshaft Position (CMP) Sensor Performance

1. The ignition is ON.
2. The engine is turning faster than 60 RPM.
3. DTC P0341 runs continuously once the above conditions are met.

The ECM determines that the CMP sensor signal is out of range for less than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

1. An intermittent CMP sensor signal may cause DTC P0341 to set. Wiggle the wiring harness with the engine running and observe the Cam Signal Missed parameter of the scan tool. If the parameter indicates anything other than 0, there is an intermittent condition. Refer to «Testing for Intermittent Conditions and Poor Connections»(ref-197325-S02683201702005101100000) and «Inducing Intermittent Fault Conditions»(ref-197325-S26763912192005101100000) in Wiring Systems.
2. If the CMP sensor signal is lost while running, the engine will operate normally. If the CMP sensor signal is not present on start-up, the engine will not start.

DTC P0341

The engine control module (ECM) replicates the signal received from the crankshaft position (CKP) sensor. This signal is sent to the fuel injection control module (FICM) through the engine speed signal circuit. The FICM uses this replicated signal to generate injection current and control the recharge of the fuel injection high voltage circuits. When cranking, the FICM has full control of the fuel injectors. The only input the FICM uses at this time is the engine speed signal from the ECM. The FICM monitors the signal along with the injection request signals from the ECM after the engine is running. If there is a problem with this signal, a DTC could set.

This diagnostic procedure supports the following DTCs

1. DTC P0370 High Resolution Circuit
2. DTC P0374 High Resolution System Performance

The engine is cranking or running.

1. The FICM does not receive a crank signal, but does receive injection requests from the ECM. OR
2. The FICM receives an invalid crank signal from the ECM.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

A missing high resolution signal will cause a no-start condition. High resistance in the position sensor low reference circuit may cause this DTC to set. If the condition is intermittent, refer to Intermittent Conditions .

DTC P0370 or P0374

The engine control module (ECM) tests the exhaust gas recirculation (EGR) flow once per ignition cycle. When the proper enabling conditions are met, the ECM will close the EGR valve and then open the EGR valve while monitoring the mass air flow (MAF) signal. An expected MAF difference should be detected between the open and closed positions. If the ECM does not see the expected MAF difference, DTC P0401 sets.

This diagnostic procedure supports the following DTC

DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient

1. DTCs P0101, P0102, P0103, P0112, P0113, P0116, P0117, P0118, P0335, P0336, P0340, P0341, P0370, P0374, P0500, P0642, P0643, P2122, P2123, P2127, P2128, P2132, P2133, P2138, P2139, P2140, P2227, P2228, P2229 are not set.
2. The engine is running for more than 0.5 seconds.
3. The ignition voltage is between 11-18 volts.
4. The calculated fuel rate is between 3-20 mm 3 . This running condition will remain enabled until the calculated fuel rate is less than 2 mm 3 or more than 25 mm 3 and will not enable again until the calculate fuel rate is between 3-20 mm 3 .
5. The intake air temperature (IAT) is more than 5.25°C (41.5°F). This running condition will remain enabled until the IAT is less than 0°C (32°F) and will not enable again until the IAT is more than 5.25°C (41.5°F).
6. The engine coolant temperature (ECT) is between 60-96.75°C (140-206.15°F). This running condition will remain enabled until the ECT is less than 57°C (134.6°F) or more than 99.75°C (211.55°F) and will not enable again until the ECT is between 60-96.75°C (140-206.15°F).
7. The barometric pressure (BARO) is more than 74 kPa. This running condition will remain enabled until the BARO is less than 72 kPa and will not enable again until 74 kPa.
8. The engine speed is between 640-820 RPM. This running condition will remain enabled until the engine speed is less than 580 RPM or more than 880 RPM and will not enable again until the engine speed is between 640-820 RPM.
9. The accelerator pedal position (APP) indicated angle is 0 percent.
10. The vehicle speed is less than 0.4 km/h (0.25 mph).
11. The power take-off (PTO) is not engaged.
12. The ECM is not in limp home mode.
13. The above conditions are present for 10 seconds.
14. DTC P0401 runs once per ignition cycle while the above conditions are met.

The MAF difference monitored by the ECM during the EGR flow test indicates an insufficient amount of EGR flow for 10 seconds.

Action Taken When the DTC Sets - California

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Action Taken When the DTC Sets - Federal

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The MIL will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0401

The exhaust gas recirculation (EGR) valve is controlled by the engine control module (ECM) through the EGR motor high control and the EGR motor low control circuits. The ECM supplies voltage that is near ignition voltage to the high and low control circuits at all times. The ECM will pulse width modulation (PWM) the low control circuit to ground when EGR is desired. The lower the pulse width, the more the valve will open. The ECM will PWM the high control circuit to ground when the EGR valve is desired closed. If the ECM detects an electrical malfunction on the control circuits, DTC P0403 will set.

This diagnostic procedure supports the following DTC

DTC P0403 Exhaust Gas Recirculation (EGR) Solenoid Control Circuit

1. The engine is running for more than 0.5 seconds.
2. The ignition voltage is between 11-18 volts.
3. The intake air temperature (IAT) is between 0-150.75°C (32-303.35°F).
4. The engine coolant temperature (ECT) is between 57-99.75°C (134.6-211.6°F).
5. The barometric pressure (BARO) is more than 72 kPa.
6. The EGR valve is commanded open.
7. DTC P0403 runs continuously once the above conditions are met.

1. The ECM detects an electrical malfunction on an EGR motor control circuit.
2. The above condition is present for more than 10 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The MIL will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0403

The engine control module (ECM) uses the exhaust gas recirculation (EGR) position sensor to determine the position of the EGR valve. The ECM sends a reference voltage through the 5-volt reference circuit to the EGR position sensor. The ECM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the EGR valve position, is sent from the sensor to the ECM through the EGR position sensor signal circuit. The ECM compares the actual EGR position with the desired EGR position when the EGR valve is commanded open or closed. If the ECM detects a variance between the actual EGR position and desired EGR position for a calibrated amount of time while the EGR valve is commanded open, DTC P0404 sets.

This diagnostic procedure supports the following DTC

DTC P0404 Exhaust Gas Recirculation (EGR) Open Position Performance

1. DTCs P0642 and P0643 are not set.
2. The engine is running for more than 0.5 seconds.
3. The ignition voltage is between 11-18 volts.
4. The intake air temperature (IAT) is between 0-150.75°C (32-303.35°F).
5. The engine coolant temperature (ECT) is between 57-99.75°C (134.6-211.6°F).
6. The barometric pressure (BARO) is more than 72 kPa.
7. The power take-off (PTO) is not engaged.
8. The desired EGR valve position is more than 3 percent.
9. DTC P0404 runs continuously when the above conditions are met.

1. The difference between the actual EGR position and the desired EGR position is more than 6 percent.
2. The above condition is present for more than 5 seconds

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0404

The engine control module (ECM) uses the exhaust gas recirculation (EGR) position sensor to determine the position of the EGR valve. The ECM sends a reference voltage through the 5-volt reference circuit to the EGR position sensor. The ECM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the EGR valve position, is sent from the sensor to the ECM through the EGR position sensor signal circuit. If the ECM detects an EGR position sensor voltage that is less than the normal operating range, DTC P0405 sets.

This diagnostic procedure supports the following DTC

DTC P0405 Exhaust Gas Recirculation (EGR) Position Sensor Circuit Low Voltage

1. DTCs P0642 and P0643 are not set.
2. The engine is running for more than 0.5 seconds.
3. The ignition voltage is between 11-18 volts.
4. The intake air temperature (IAT) is between 0-150.75°C (32-303.35°F).
5. The engine coolant temperature (ECT) is between 57-99.75°C (134.6-211.6°F).
6. The barometric pressure (BARO) is more than 72 kPa.
7. DTC P0405 runs continuously once the above conditions are met.

1. The EGR position sensor voltage is less than 0.25 volts.
2. The above condition is present for more than 10 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The MIL will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0405

The engine control module (ECM) uses the exhaust gas recirculation (EGR) position sensor to determine the position of the EGR valve. The ECM sends a reference voltage through the 5-volt reference circuit to the EGR position sensor. The ECM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the EGR valve position, is sent from the sensor to the ECM through the EGR position sensor signal circuit. If the ECM detects an EGR position sensor voltage that is more than the normal operating range, DTC P0406 sets.

This diagnostic procedure supports the following DTC

DTC P0406 Exhaust Gas Recirculation (EGR) Position Sensor Circuit High Voltage

1. DTCs P0642 and P0643 are not set.
2. The engine is running for more than 0.5 seconds.
3. The ignition voltage is between 11-18 volts.
4. The intake air temperature (IAT) is between 0-150.75°C (32-303.35°F).
5. The engine coolant temperature (ECT) is between 57-99.75°C (134.6-211.6°F).
6. The barometric pressure (BARO) is more than 72 kPa.
7. DTC P0406 runs continuously once the above conditions are met.

1. The EGR position sensor voltage is more than 4.75 volts.
2. The above condition is present for more than 10 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The MIL will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0406

The engine control module (ECM) adjusts the fuel delivery in order to control crankshaft speed at idle. If the ECM detects the engine speed is incorrect for the amount of fuel that is delivered, DTC P0506 sets.

This diagnostic procedure supports the following DTC

DTC P0506 Idle Speed Low

1. DTCs P0016, P0117, P0118, P0335, P0336, P0340, P0341, P0500, or P0700 are not set.
2. The engine is running at idle for more than 10 seconds.
3. The idle is stable to within 20 RPM.
4. The fuel delivery is less than 2.5 mm 3 per cylinder of target quantity.
5. The engine coolant temperature (ECT) is more than 50°C (122°F).
6. The intake air temperature (IAT) is less than 20°C (68°F).
7. The vehicle speed is 0 mph.
8. The throttle angle is 0 percent.
9. DTC P0506 runs continuously in a 250 ms test loop.

The actual idle speed is more than 100 RPM under the target idle speed.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0506

The engine control module (ECM) adjusts the fuel delivery in order to control crankshaft speed at idle. If the ECM detects the engine speed is incorrect for the amount of fuel that is delivered, DTC P0507 sets.

This diagnostic procedure supports the following DTC

DTC P0507 Idle Speed High

1. DTCs P0016, P0117, P0118, P0335, P0336, P0340, P0341, P0500, or P0700 are not set.
2. The engine is running at idle for more than 10 seconds.
3. The idle is stable to within 20 RPM.
4. The fuel delivery is less than 2.5 mm 3 per cylinder of target quantity.
5. The engine coolant temperature (ECT) is more than 50°C (122°F).
6. The intake air temperature (IAT) is less than 20°C (68°F).
7. The vehicle speed is 0 mph.
8. The throttle angle is 0 percent.
9. DTC P0507 runs continuously in a 250 ms test loop.

The actual idle speed is more than 100 RPM over the target idle speed.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

Inspect for one of the following

1. A crankcase overfill causing oil to be forced through the positive crankcase ventilation (PCV) system
2. An aftermarket performance kit using an external fuel source
3. An engine mechanical condition

DTC P0507

Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed.

This diagnostic procedure supports the following DTCs

1. DTC P0601 Control Module Read Only Memory (ROM)
2. DTC P0602 Control Module Not Programmed
3. DTC P0603 Control Module Long Term Memory Reset
4. DTC P0604 Control Module Random Access Memory (RAM)
5. DTC P1621 Control Long Term Memory Performance
6. DTC P2610 Control Module Ignition Off Timer Performance

1. DTC P0601, P0603, P0604, and P1621 run during power up.
2. DTC P0602 and P2610 run continuously.

These codes will set when there is incomplete programming or an internal failure within the ECM within 15 seconds.

DTC P0601, P0602, and P0604

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

DTC P0603 and P1621

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The MIL will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center (DIC), if equipped, may display a message.

DTC P2610

1. The control module illuminates the MIL on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

DTC P0601, P0602, P0604, and P2610

1. The control module turns OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0603 and P1621

1. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Clear the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: A DTC P0602 indicates the ECM is not programmed.

DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683, or P2610

This diagnostic applies to internal microprocessor integrity conditions within the fuel injection control module (FICM).

This diagnostic procedure supports the following DTCs

1. DTC P0611 Fuel Injector Control Module Performance
2. DTC P1293 Injector Circuit Low to High Current Transition Time Bank 1
3. DTC P1294 Injector Circuit Low to High Current Transition Time Bank 2
4. DTC P1295 Injector Circuit High to Low Current Transition Time Bank 1
5. DTC P1296 Injector Circuit High to Low Current Transition Time Bank 2
6. DTC P1658 Fuel Injector Control Module Driver Performance
7. DTC P1687 Fuel Injector Control Module Driver Stuck On

1. The ignition must be on for DTC P0611, P1293, P1294, P1295, P1296, P1658, P1687 to run.
2. DTC P0611, P1293, P1294, P1295, P1296, P1658, P1687 runs continuously once the above conditions are met.

These codes will set when there is an internal failure in the FICM for less than 1 second.

Action Taken When DTC P1293, P1294, P1295, P1296, P1658, or P1687 Sets

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

Action Taken When the DTC P0611 Sets

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0611, P1293, P1294, P1295, P1296, P1658, or P1687

The engine control module (ECM) monitors the condition of the ignition relay control circuit. If the ECM senses excessive voltage on this circuit, DTC P0612 will set.

This diagnostic procedure supports the following DTC

DTC P0612 Fuel Injector Control Module (FICM) Relay Control Circuit

The ignition is ON.

DTC P0612 runs continuously once the above condition is met.

The feedback voltage does not match the output state for more than 1 second.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

If the engine starts, the ignition relay control circuit is shorted to power intermittently.

DTC P0612

The engine control module (ECM) provides 5 volts to the following sensors

1. The oil pressure sensor
2. The exhaust gas recirculation (EGR) valve
3. The accelerator pedal position (APP) 1 sensor
4. The rail pressure sensor

These 5-volt reference circuits are independent of each other outside the ECM, but are bussed together inside the ECM. Therefore, a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The ECM monitors the voltage on the 5-volt reference circuit. If the ECM detects a low voltage condition, DTC P0642 sets.

This diagnostic procedure supports the following DTC

DTC P0642 5-Volt Reference 1 Circuit Low Voltage

1. The ignition is ON.
2. DTC P0642 runs continuously.

1. The ECM detects the 5-volt reference 1 circuit voltage is less than 4.7 volts.
2. The above condition is present for 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0642

The engine control module (ECM) provides 5 volts to the following sensors

1. The oil pressure sensor
2. The exhaust gas recirculation (EGR) valve
3. The accelerator pedal position (APP) 1 sensor
4. The rail pressure sensor

These 5-volt reference circuits are independent of each other outside the ECM, but are bussed together inside the ECM. Therefore, a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The ECM monitors the voltage on the 5-volt reference circuit. If the ECM detects a high voltage condition, DTC P0643 sets.

This diagnostic procedure supports the following DTC

DTC P0643 5-Volt Reference 1 Circuit High Voltage

1. The ignition is ON.
2. DTC P0643 runs continuously.

1. The ECM detects the 5-volt reference 1 circuit voltage is more than 5.2 volts.
2. The above condition is present for longer than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0643

The malfunction indicator lamp (MIL) is located on the instrument panel cluster (IPC). The MIL informs the driver that an emission system fault has occurred and that the engine control system requires service. The control module monitors the MIL control circuit for conditions that are incorrect for the commanded state of the MIL. For example, a failure condition exists if the control module detects low voltage when the MIL is commanded OFF, or high voltage when the MIL is commanded ON. If the control module detects an improper voltage on the MIL control circuit, DTC P0650 will set.

This diagnostic procedure supports the following DTC

DTC P0650 Malfunction Indicator Lamp (MIL) Control Circuit

1. The ignition is ON.
2. The ignition voltage is between 6-18 volts.
3. DTC P0650 runs continuously once the above conditions are met.

1. The control module detects that the commanded state of the MIL driver and the actual state of the control circuit do not match.
2. The conditions are present for a minimum of 30 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The numbers below refer to the step numbers on the diagnostic table.

1. 4: This step tests for a short to ground in the MIL control circuit. With the Engine Control Module (ECM) disconnected and the ignition ON, the MIL should be OFF.
2. 5: This step tests for a short to voltage on the MIL control circuit. With the fuse removed, there should be no voltage on the MIL control circuit.

DTC P0650

The engine control module (ECM) provides 5 volts to the following sensors

1. The boost sensor
2. The accelerator pedal position (APP) 2 sensor
3. The turbocharger vane position sensor
4. The A/C refrigerant pressure sensor
5. The barometric pressure (BARO) sensor

These 5-volt reference circuits are independent of each other outside the ECM, but are bussed together inside the ECM. Therefore, a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The ECM monitors the voltage on the 5-volt reference circuit. If the ECM detects a low voltage condition, DTC P0652 sets.

This diagnostic procedure supports the following DTC

DTC P0652 5-Volt Reference 2 Circuit Low Voltage

1. The ignition is ON.
2. DTC P0652 runs continuously.

1. The ECM detects the 5-volt reference circuit 2 voltage is less than 4.7 volts.
2. The above condition is present for 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0652

See also:
• Engine Controls Schematics
• Engine Control Module (ECM) Connector End Views
• Engine Controls Connector End Views
• Intermittent Conditions
• DTC P0653
• Turbocharger Replacement
• Turbocharger Cleaning and Inspection
• Engine Compression Test
• Fuel Injector Balance Test with Tech 2 (with Automatic Transmission)
• Exhaust Gas Recirculation (EGR) System Cleaning
• Engine Will Not Crank - Crankshaft Will Not Rotate
• Service Programming System (SPS)
• DTC P0404