Rear differential lock failure warning light illumination circuit system check (Differential Lock)

1. Differential lock control system check

Refer to "53.Driveline Control 3A.Troubleshooting(Differential Lock) diagnostic system check - differential lock controls".

2. DTC verification

1) Observe the DTC information for the rear differential lock control unit with a scan tool. Is a DTC set?

Yes

Go to the applicable DTC diagnosis.

No

=>Go to Instrument panel cluster setting verification.

3. Instrument panel cluster setting verification

1) Connect the scan tool.

2) Turn ON the ignition switch.

3) Display the Module Information with a scan tool.

4) Observe the Diff Lock Fail Indicator Light setting on the scan tool. Does the Diff Lock Fail Indicator Light setting show Available?

Yes

Replace the instrument panel cluster.

Refer to "9.Body, Cab, Accessories 9E.Instrumentation, Driver Info. instrument panel cluster removal".

Refer to "9.Body, Cab, Accessories 9E.Instrumentation, Driver Info. instrument panel cluster installation".

Refer to "9.Body, Cab, Accessories 9E.Instrumentation, Driver Info. instrument panel cluster setting".

=>Go to Repair verification.

No

Perform programming of the instrument panel cluster.

Refer to "9.Body, Cab, Accessories 9E.Instrumentation, Driver Info. instrument panel cluster setting".

=>Go to Repair verification.

4. Repair verification

1) Turn OFF the ignition switch.

2) Turn ON the ignition switch.

3) Check whether the rear differential lock failure light turns OFF after illuminating for approximately 3 seconds.