Diagnostic Test
- ACTIVE DTC
- Turn the ignition on.
- Using the scan tool, actuate the EGR Valve.
- Using the scan tool, read active DTCs.
Is the DTC active?
Yes
- Go To 2
No
- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- CHECK THE (K682) EGR CONTROL (+) CIRCUIT FOR A SHORT TO VOLTAGE
- Turn the ignition off.
- Disconnect the EGR Valve harness connector.
- Disconnect the PCM C2 harness connector.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 the GPEC Diagnostic Adaptor to perform the diagnosis.
- Connect the (special tool #10436, Adapter, GPEC Diagnostic).
- Measure the resistance between the (K682) EGR Control (+) circuit and all other circuits at the GPEC Adaptor.
Is the resistance above 10k Ohms between the (K682) EGR Control (+) circuit and all other circuits?
Yes
- Go To 3
No
- Repair the short to between the (K682) EGR Control (+) circuit and the circuit that measured below 10k Ohms.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK THE (K684) EGR CONTROL (-) CIRCUIT FOR A SHORT TO VOLTAGE
- Measure the resistance between the (K684) EGR Control (-) circuit and all other circuits at the GPEC Adaptor.
Is the resistance above 10k Ohms between the (K684) EGR Control (-) circuit and all other circuits?
Yes
- Go To 4
No
- Repair the short to between the (K684) EGR Control (-) circuit and the circuit that measured below 10k Ohms.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance between the (K684) EGR Control (-) circuit and all other circuits at the GPEC Adaptor.
- EGR VALVE
- Reconnect the PCM C2 harness connector.
- Turn the ignition on.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.
- Using the scan tool, actuate the EGR Valve.NOTE:
The scan tool should display the P2425-EGR COOLING VALVE CONTROL CIRCUIT/OPEN DTC as active or pending with the EGR Valve harness connector unplugged.
Does the scan tool display the DTC as described above?
Yes
- Go To 5
No
- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- POWERTRAIN CONTROL MODULE (PCM)
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Valve and the PCM.
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL . Refer to PCM/ECM REPROGRAMMING - GAS .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .