Headlight motor problems

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Headlight motor problems are common on the Pontiac Fiero because all Fieros use pop-up headlight doors driven by electric motors.

The Fiero used two different factory headlight systems. The 1984-1986 cars use the first-generation system, while the 1987-1988 cars use the second-generation system. Diagnosis and repair depend on which system is installed.

Overview

Headlight motor problems may include one or both headlight doors failing to open, failing to close, moving slowly, making noise, stopping partway, or continuing to run after reaching the open or closed position.

Because the two Fiero headlight systems are different, parts and diagnostic steps should not be mixed without confirming the model year and system type.

Symptoms

Common symptoms include:

  • One headlight door does not open.
  • One headlight door does not close.
  • Both headlight doors do not move.
  • A headlight motor runs but the door does not move.
  • A headlight motor keeps running after the door is open or closed.
  • A headlight door moves slowly or intermittently.
  • A headlight door opens or closes only partway.
  • A clicking, grinding, or rattling sound is heard from the motor area.

1984-1986 headlight system

The 1984-1986 Fiero uses the first-generation headlight system. This system uses early-style motors and relays.

Related topics:

1987-1988 headlight system

The 1987-1988 Fiero uses the second-generation headlight system. This system uses later-style motors and a headlight control module.

Related topics:

Common causes

Headlight motor problems may be caused by:

  • Worn motor gears
  • Failed motor bushings
  • Worn internal contacts
  • Failed relays
  • Failed headlight control module
  • Bad grounds
  • Damaged wiring
  • Poor connectors
  • Binding headlight doors
  • Worn linkage parts
  • Incorrect adjustment
  • Weak battery or low system voltage

Mechanical diagnosis

Before assuming an electrical fault, check for mechanical binding.

Inspect the headlight door, linkage, pivot points, motor mounting, and surrounding body panels. A motor may fail to move the door correctly if the mechanism is jammed, misaligned, damaged, or obstructed.

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Electrical diagnosis

Electrical diagnosis depends on the headlight system generation.

Basic checks include:

  1. Identify whether the car has the 1984-1986 or 1987-1988 system.
  2. Check the headlight fuse or fusible links as applicable.
  3. Check battery voltage.
  4. Check grounds and connectors.
  5. Check whether the problem affects one side or both sides.
  6. Check the relays or control module.
  7. Check motor power and ground.
  8. Inspect the motor internally if power and ground are present.

Repair

Many headlight motor problems can be repaired by rebuilding the motors, replacing worn gears or bushings, cleaning contacts, repairing wiring, replacing relays, or replacing the headlight control module.

Related topics:

Notes

The 1984-1986 and 1987-1988 systems are different. Parts, wiring, control methods, and common failures differ between the two generations.

Always identify the system before ordering parts or following a repair procedure.

See also