Component Tests and General Diagnostics

1. Check the RR Defog and the HVAC Fuses by visual inspection.
2. If one or more of the grid lines do not heat, refer to Stationary Windows for grid line repair procedures. Windows
3. If the Panel Light is inoperable with the Headlamp Switch in the PARK or HEAD positions, check the bulb and the wiring to bulb. Refer to Interior Lights Dimming. Lighting and Horns
4. If the Rear Defogger ON Indicator lights continuously or does not light at all, but Rear Defogger operates normally, replace the Heater-A/C and Rear Defogger Control Assembly. Refer to Heater-A/C Control. Heating and Air Conditioning
5. If the Rear Defogger does not stay on for the ten minute/five minute time periods, replace the Heater-A/C and Rear Defogger Control Assembly. Refer to Heater-A/C Control.
6. If the Rear Defogger does not turn off replace the Heater-A/C and Rear Defogger Control Assembly. Refer to Heater-A/C Control.
^ Check for a broken (or partially broken) wire inside of the insulation which could cause system failure but prove good in a continuity/voltage check. Refer to Troubleshooting Procedures.
^ Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems. Refer to Troubleshooting Procedures. Diagnostic Aids