Important: For the inside rearview mirror with the automatic
day-night feature or the rear window defogger (w/o CJ2), review the system operation
in order to familiarize yourself with the system functions. Refer to 
Rear Window Defogger Description and Operation 
.
For the rear
window defogger (w/CJ2) system, perform the following steps before using the symptom
tables:
- Perform 
Diagnostic System Check - Vehicle 
 in Vehicle DTC Information before using the symptom tables in order to
verify that the following conditions are true:
 
| •  | The control modules can communicate via the serial data link. | 
 
- Review the rear window defogger system operation in order to familiarize
yourself with the system functions. Refer to 
Rear Window Defogger Description and Operation 
.
 
Visual/Physical Inspection
|     •  | Inspect for aftermarket devices which could affect the operation of the
rear window defogger or the automatic day-night feature of the inside rearview mirror.
Refer to 
Checking Aftermarket Accessories 
 in
Wiring Systems. | 
 
|     •  | Inspect the easily accessible system components for obvious damage or
for conditions which could cause the symptom. | 
 
Intermittent
Bad electrical connections or wiring may be the cause of intermittent conditions.
Refer to 
Testing for Intermittent Conditions and Poor Connections 
 in Wiring Systems.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order to
diagnose the symptom: