P0403

P0403-EGR SOLENOID CIRCUIT





For a complete wiring diagram refer to Diagrams/Electrical.


- When Monitored:

Engine running. Battery voltage greater than 10 volts.

- Set Condition:

The EGR solenoid control circuit is not in the expected state when requested to operate by the PCM. One Trip Fault.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.


Diagnostic Test


1. DTC IS ACTIVE

Turn the ignition on.

With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).

With the scan tool, actuate the EGR Valve Solenoid Duty Cycle to 79.9%.

With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition


2. (K35) EGR CONTROL CIRCUIT SHORTED TO VOLTAGE





Turn the ignition off.

Disconnect the EGR Valve Assembly connector.

Disconnect the Powertrain Control Module (PCM) connector.

Turn the ignition on.

Measure the voltage of the (K35) EGR Control circuit in the EGR Valve Assembly harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (K35) EGR Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go to 3


3. (K35) EGR CONTROL CIRCUIT SHORTED TO GROUND





Turn the ignition off.

Measure the resistance between ground and the (K35) EGR Control circuit in the EGR Valve Assembly harness connector.

Is the resistance above 100 ohms?

Yes

- Go to 4

No

- Repair the short to ground in the (K35) EGR Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


4. (K35) EGR CONTROL CIRCUIT OPEN OR HIGH RESISTANCE





CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K35) EGR Control circuit between the EGR Valve Assembly harness connector and the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

- Go to 5

No

- Repair the excessive resistance in the (K35) EGR Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


5. (Z904) GROUND CIRCUIT OPEN OR HIGH RESISTANCE





Using a 12 volt test light connected to 12 volts, check the (Z904) Ground circuit in the EGR Valve Assembly harness connector.


NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go to 6

No

- Repair the (Z904) Ground circuit for an open circuit or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


6. EGR VALVE ASSEMBLY

Connect the Powertrain Control Module (PCM) connector.

Turn the ignition on.

With the scan tool, actuate the EGR Valve Solenoid Duty Cycle.

Select the Duty Cycle reading of 79.9%

Using a 12 volt test light connected to ground, check the (K35) EGR Control circuit in the EGR Valve Assembly harness connector.


NOTE: If the DTC is active, the actuation test may not be allowed by the PCM. If may be necessary to clear the DTCs before starting the actuation.


NOTE: The voltage supplied to the solenoid circuit during the actuation may be less than battery voltage. The test light should be illuminated, but may not be as bright as a direct connection to the battery.

Is the test light illuminated during the actuation?

Yes

- Replace the EGR Valve Assembly.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go to 7


7. PCM

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Valve Assembly and the Powertrain Control Module (PCM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test