Symptoms

Important:

1. Perform the A Diagnostic System Check
^ There are no DTCs set.
^ The control module(s) can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to Transfer Case Circuit Description and Transfer Case Description.

Visual/Physical Inspection
^ Inspect for aftermarket devices which could affect the operation of the Manual Selectable 4 Wheel Drive System. Refer to Checking Aftermarket Accessories in Diagrams/Diagnostic Aids.
^ Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
^ Ensure all mechanical components are operative before diagnosing the electrical portion of the system.
^ In order to determine whether the vehicle is in two-wheel drive or four-wheel drive, lift the vehicle so that the wheels can spin freely. Turning the rear drive shaft and the front drive shaft turns with the front, the vehicle is in 4WD.
^ Make sure that the 4WD fuse is not open. If open, locate and repair the source of the overload. Refer to Testing for Short to Ground in Diagrams/Diagnostic Aids. Replace the fuse.

Intermittent
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent and Poor Connections in Diagrams/Diagnostic Aids.

Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:
^ Four- Wheel-Drive Does Not Disengage Four-Wheel-Drive Does Not Disengage
^ Four- Wheel-Drive Does Not Engage Four-Wheel-Drive Does Not Engage
^ Four- Wheel-Drive Indicator Does Not Light Four-Wheel-Drive Indicator Does Not Light
^ Four- Wheel-Drive Indicator Does Not Turn Off Four-Wheel-Drive Indicator Does Not Turn Off