A Preliminary Information

IMPORTANT: Review the system operation in order to familiarize yourself with the system functions. Refer to:
^ Rear Window Defogger Operation
^ Automatic Day-Night Mirror Operation
^ Rear Window Defogger Circuit 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 Always On - Rear Window
^ Defogger Inoperative - Rear Window
^ Defogger Indicator Inoperative
^ Defoggers and Heated Mirrors Always On
^ Defogger Grid Lines Diagnosis
^ Mirrors - Automatic Day-Night Inoperative