1989 Pontiac SafariFACTORY OEM SERVICE PROCEDURE

Control Test: Firebird

  1. Turn ignition switch to "RUN" position. Hold defogger switch to "ON" position. Turn parking lights on and interior lights to maximum brightness.
  2. With defogger control connected, connect voltmeter between Pink/Black wire and ground. Battery voltage should be present. If not, check wire for open circuit. If wire is okay, check "GAUGES" fuse.
  3. Connect voltmeter between Light Blue wire and ground. Voltmeter should read battery voltage. If not, replace defogger control switch.
  4. Connect voltmeter between Purple/White wire and ground. Voltmeter should read battery voltage. If not, check wire for open circuit. If wire is okay, check defogger timer/relay.
  5. Connect voltmeter between Gray wire and ground. Voltmeter should read battery voltage. If not, check "INST LP" fuse. If fuse is okay, check Gray wire for open circuit.
  6. Connect voltmeter between Gray and Black wire. Voltmeter should read battery voltage. If not, check Black wire for open circuit. Check that ground is clean and tight. If both checked out okay, replace panel light.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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