Important: The following steps must be performed before using the symptom tables for proper
rear window defogger system diagnosis:
- Perform the
Diagnostic System Check - Vehicle
in Vehicle DTC Information, before
using the symptom tables in order to verify that all of the following are true:
• | The control modules can communicate via the serial data link. |
- Review the 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 compass. Refer to
Checking Aftermarket Accessories
in Wiring Systems. |
• | Inspect the easily accessible or visible system components for obvious
damage or conditions which could cause the symptom. |
Intermittent
Faulty 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: