Diagnostic Test

WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

1) ACTIVE DTC
NOTE: You must diagnose any Solenoid circuit (Low or High) DTCs first if set along with this DTC before continuing.

Ignition on, engine not running.

With the DRBIII®, read DTCs.

Is the DTC active at this time?

Yes
1. Go To step 2).
No
1. Go To step 4).
2) WIRING HARNESS INSPECTION
Inspect the wiring harness from both solenoids to the FDCM. Ensure that the harness has routed correctly.

Inspect the FDCM harness connector and Differential Solenoid connectors. Ensure the terminals are clean and no damage is present.

Was the wiring harness and connectors OK?

Yes
1. Repair as necessary.
2. Perform FDCM VERIFICATION TEST .
No
1. Go To step 3).
2. Perform FDCM VERIFICATION TEST .
3) INSPECTION DIFFERENTIAL
Ensure the Differential is operating properly. Refer to Service Information.

Inspect the Differential for external fluid leaks. Repair as necessary, refer to Service Information.

Is the Differential operating properly?

Yes
1. Replace the Front Differential Solenoid.
2. Perform FDCM VERIFICATION TEST .
No
1. Repair as necessary.
2. Perform FDCM VERIFICATION TEST .
4) INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.

Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.

Wiggle test the wiring harness and connectors while checking for shorted and open circuits.

Using the DRBIII®, monitor the data related to this circuit while performing the wiggle test. Look for the data to change or for the DTC to reset.

Were there any problems found?

Yes
1. Repair as necessary.
2. Perform FDCM VERIFICATION TEST .
No
1. Test Complete.