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Home >> Oldsmobile >> 1998 >> Cutlass Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Heated Glass/Defoggers >> Rear Window Defogger >> Testing >> Defogger System Tests >> System Check

System Check

  1. Visually inspect RR DEFOG (30-amp) and HTR A/C IGN (10-amp) fuses. By feel, check for any grid lines not heating. If any grid lines are not heating, see GRID FILAMENT TEST  .
  2. If panel indicator light is inoperable with headlight switch in PARK or HEAD, check bulb and wiring to bulb.
  3. If rear defogger ON indicator lights continuously or does not light at all, but rear defogger operates normally, replace A/C-heater control assembly.
  4. Check for broken (or partially broken) wire inside of insulation casing system failure but proving good in continuity/voltage check.
  5. Check for proper installation of aftermarket electronic equipment which may affect integrity of other systems.