General

1. Refer to "Defogger" for diagnosis of the Rear Window Defogger controls. Testing and Inspection
2. Refer to "Instrument Panel Dimming for diagnosis of the Instrument Panel Dimming System. Testing and Inspection
3. CHECK for broken (or partially broken) wire inside of insulation which could cause system malfunction but prove "GOOD" in a Continuity/Voltage check with a system disconnected. These Circuits may be intermittent or resistive when loaded. and if possible should be checked by monitoring for a Voltage drop with the system operational (under load).
4. CHECK for proper installation of aftermarket electronic equipment which may affect the integrity of other systems (Refer "Troubleshooting Procedures"). Diagnostic Aids