Preliminary Information

IMPORTANT: The following steps must be completed before using the symptom tables.
1. Perform the A Diagnostic System Check - Defogger or A Diagnostic System Check - Automatic Day-Night Mirror, before using the Symptom Tables in order to verify that the following are true:
^ 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 the following:
^ Rear Window Defogger Description
^ Rear Window Defogger Circuit Description
^ Automatic Day-Night Mirror Description
^ Automatic Day-Night Mirrors Circuit Description

VISUAL/PHYSICAL INSPECTION
^ Inspect for aftermarket devices which could affect the operation. Refer to Checking Aftermarket Accessories in Diagrams.
^ 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 and Poor Connections in Diagrams.

SYMPTOM LIST
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:
^ Defogger Inoperative - Rear Window (W/O UY4, UE7, UE9) or Defogger Inoperative - Rear Window (W/UY4, UE7, UE9)
^ Defogger Grid Lines Diagnosis
^ Mirrors - Automatic Day-Night Inoperative
^ Mirrors - Compass Inoperative or Inaccurate

For a description of the RPO Code(s) shown in this image/article refer to the RPO Code List found at Vehicle/Application ID RPO Codes