Cruze

DTC P0403-P0406 or P042E

Voltage is provided to the exhaust gas recirculation (EGR) valve by the ignition voltage circuit through fuse F47. Ground is provided to the EGR valve on the control circuit by a low side driver within the engine control module (ECM). The ECM monitors the voltage on the control circuit of the EGR valve to determine if a malfunction is present.

The ECM monitors the position of the EGR valve through the EGR valve position sensor. The EGR valve position sensor sends a feedback voltage on the signal circuit to the ECM. The EGR position sensor voltage varies depending on the position of the EGR valve.

The EGR valve utilizes the following circuits:

P0403 00, P0404 00, and P042E

P0405 00 and P0406 00

P0403 00

The ECM detects an open, short to ground or voltage on the control circuit of the EGR valve.

P0404 00

The ECM detects a difference between the actual EGR position and the commanded EGR position of more than 15%.

P0405 00

The ECM detects that the EGR position sensor percentage is less than 2%.

P0406 00

The ECM detects that the EGR position sensor percentage is greater than 98%.

P042E 00

The ECM detects the difference between the actual EGR position and the learned EGR position is greater than 10%.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Refer to Exhaust Gas Recirculation (EGR) System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Engine running, observe the DTC information with a scan tool. Verify that DTCs P0651 00 is not set.

⇒	If DTC P0651 00 is set, refer to DTC P0641, P0651, or P0697 .

Note: The scan tool EGR position sensor parameter will display less than 100% when the EGR is commanded to 100%.

2. Ignition ON, observe the scan tool EGR Position Variance parameter while commanding the EGR valve to 100%. The reading should be less than 15%.
3. Engine running, observe the scan tool EGR Position Sensor percentage parameter. The reading should be less than 4%.
4. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

1. Ignition OFF, disconnect the harness connector at the Q14 Exhaust Gas Recirculation Valve.
2. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal E and ground.

⇒	If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition voltage circuit fuse F47 is open, test all components connected to the ignition voltage circuit and replace as necessary.

3. Connect a test lamp between the control circuit terminal C and the ignition voltage circuit terminal E.
4. Command the EGR Solenoid Valve from 0-100% with a scan tool. The test lamp should respond to the scan tool commands.

⇒	If test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

5. Ignition OFF, test for less than 1 Ω of resistance between the low reference circuit terminal B and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

6. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal D and ground.

⇒	If less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

7. Verify the scan tool EGR Position Sensor parameter is less than 3%.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

8. Install a 3 A fused jumper wire between the signal circuit terminal A and the 5 V reference circuit terminal D. Verify the scan tool EGR Position Sensor parameter is greater than 95%.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

9. If all circuits test normal, test or replace the Q14 Exhaust Gas Recirculation Valve.

Static Test

1. Ignition OFF, disconnect the harness connector at the Q14 Exhaust Gas Recirculation Valve.
2. Test for 6-10 Ω of resistance between the ignition voltage terminal E and control circuit terminal C.

⇒	If not within the specified range, replace the Q14 Exhaust Gas Recirculation Valve.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.