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Headlight Doors - Automatic: Testing

CAUTION: Never contact battery voltage across Gray and White wires into actuators. This can cause damage to internal reaction switches.
NOTE: Fusible links for headlight door system are located on right hand rear of engine at starter solenoid and in front lights harness near the light switch.
  1. Check voltage at light switch. Turn ignition switch "ON". Terminal B (Red) should read battery voltage at all times. Terminal E (Yellow) should read battery voltage with light switch in "HEAD" position, and 0 volts with switch in "OFF" or "PARK". Terminal J (Gray) should read battery voltage in the "OFF" position and 0 volts in "PARK" or "HEAD" position. If voltage at terminal B is incorrect, check wiring. If E or J is incorrect, replace light switch.
  2. If one headlight door is not operational, measure voltage to ground at the headlight door relays. Turn ignition "OFF". For Connector C2, terminal A (Red) should read battery voltage at all times. Terminal C (Black) should read 0 volts at all times. Terminal B (Yellow) should read battery voltage with light switch in "HEAD" position and 0 volts in all others.
  3. For Connector C1, terminal A (White) should read 0 volts at all times, and terminal B (Dark Green) should read battery voltage with light switch in "HEAD" position and 0 volts in all others. If any voltages are incorrect, check wiring. If all are correct, replace headlight door relay.
  4. Measure voltage at the headlight door motor. Turn ignition "OFF". With light switch in the "OFF" position, terminal A (Gray LH or Red RH) should read battery voltage. In the "HEAD" or "PARK" positions, these terminals should read 0 volts. In any light switch position, terminal B (White LH or Dark Green/White RH) should read 0 volts. Terminal C (Dark Green LH or White/Black RH) should read battery voltage in the "HEAD" position, and 0 volts in any other. If voltage at B or C is incorrect, check wiring before replacing headlight door motor. If terminal A is incorrect, check isolation relay.
  5. Measure voltage at the isolation relay. Terminal A (Yellow) should read battery voltage with light switch in the "HEAD" position, and 0 volts in the "OFF" or "PARK" position. Terminal B (Gray) should read battery voltage in the "OFF" position and 0 volts in "HEAD" or "PARK". Terminal C (Black) should always read 0 volts. Terminal D (Red) should read 0 volts only in "HEAD" or "PARK" and battery voltage in the "OFF" position. If voltages at terminals A and B are incorrect, check wiring. If C and D are incorrect, replace isolation relay.