Transfer Case: Testing and Inspection

ON-BOARD DIAGNOSTIC SYSTEM INSPECTION








FAIL MODE FUNCTION
The warning alarm will sound if a malfunction is found in the change motor or electrical circuit. While in the fail mode, the warning alarm will sound whenever the 4WD/2WD shift switch or differential lock switch is activated. The fail mode function is canceled when the ignition switch is turned to OFF. If a malfunction occurs in either of the position switches while the change motor is running, the 4WD control module sets the mode to 2WD. If a malfunction occurs in either of the limit switches while shifting, the 4WD control module sets the motor step position.






CAUTION MODE FUNCTION

The caution alarm will sound as shown if the 4WD/2WD switch is activated while driving in 4WD (Locked) mode. The proper sequence is to first turn off the center differential lock switch to set 4WD (Free) mode; then activate the 4WD/2WD shift switch to set 2WD mode.





ELECTRICAL SIGNAL INSPECTION
Check the electrical signals to/from the 4WD control module.






















SYMPTOM OPERATION INSPECTION






































SYMPTOM TROUBLESHOOTING