Diagnostic Test
- VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
- Ignition on, engine not running.
- With a scan tool, read DTCs and record the related Freeze Frame data if any DTC(s) are present.
- Whether or not any DTC(s) are present you will want to check the following items which may assist in repairing the customer's complaint successfully.
- Check the vehicles repair history.
- If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
- Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
- Check for any service bulletin(s) related to the customer's complaint or DTC(s).
- If a service bulletin applies, follow the instructions per the service bulletin.
Choose the following scenario that best applies.
The service bulletin repaired the customer's complaint.
- Testing complete.
A DTC is present, no service bulletins apply, or the service bulletin didn't repair the customer's complaint.
- Go to step 2
- ACTIVE DTC
- Ignition on, engine not running.
- With a scan tool, read DTCs.
Is the DTC active at this time?
Yes
- Go to step 3
No
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
- EVAP PURGE SOLENOID OPERATION
- Turn the ignition off.
- Disconnect the EVAP Purge Solenoid harness connector.
- Ignition on, engine not running.
- Using a 12-volt test light, jump across the EVAP Purge Solenoid harness connector.
- With the scan tool, actuate the EVAP Purge Solenoid.
Does the test light flash on and off?
Yes
- Go to step 4
No
- Go to step 8
- EVAP PURGE SOLENOID LEAKS/STUCK OPEN
- Turn the ignition off.
- Connect the EVAP Purge Solenoid harness connector.
- Disconnect the vacuum hoses at the EVAP Purge Solenoid.NOTE: After disconnecting the EVAP Purge Solenoid vacuum connections, inspect the lines and solenoid for any signs of contamination from the EVAP Canister. This may indicate a faulty check valve. Replace/repair as necessary.
- Using a hand vacuum pump, apply 10 in Hg to the "CAN" of the EVAP Purge Solenoid.NOTE: Monitor the vacuum gauge for at least 15 seconds.
Does the EVAP Purge Solenoid hold vacuum?
Yes
- Go to step 5
No
- Replace the EVAP Purge Solenoid.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
- NVLD SWITCH OPERATION
- Ignition on, engine not running.
- Using the scan tool, monitor the NVLD Switch State with the vacuum pump still installed and holding vacuum.
Does the scan tool display the NVLD state OPEN?
Yes
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Go to step 6NOTE: Remove the vacuum pump and connect the vacuum hose before continuing.
- NVLD ASSEMBLY
- Disconnect the NVLD electrical connector.
Does the Switch change from CLOSED to OPEN?
Yes
- Replace the NVLD Assembly.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Go to step 7
- Disconnect the NVLD electrical connector.
- (K107) SIGNAL CIRCUIT SHORTED TO GROUND
- Turn the ignition off.
- Disconnect the C3 PCM harness connector.
- Measure the resistance between ground and the (K107) NVLD Switch Signal circuit in the NVLD Assembly harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (K107) NVLD Switch Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Go to step 9
- (K52) EVAP PURGE SOLENOID CONTROL CIRCUIT SHORTED TO GROUND
- Turn the ignition off.
- Disconnect the C3 PCM harness connector.
- Measure the resistance between ground and the (K52) EVAP Purge Solenoid Control circuit in the EVAP Purge Solenoid harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (K52) EVAP Purge Sol Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Go to step 9
- PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Replace and program the Powertrain Control Module per Service Information.
- Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
- Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.