Mid America Motorworks C4 Corvette Headlight Motor Troubleshooting & Installation Guide

Keep your 1984–1996 Corvette C4 pop-up headlights working smoothly with proper diagnosis and installation.

At Mid America Motorworks, we know the signature pop-up headlights are one of the most iconic features of the C4 Corvette. But with age, factory motors and wiring can fail, leaving owners with jittery, stuck, or non-functioning headlights. Before installing a new C4 Corvette headlight motor or upgrade kit, it’s critical to inspect and correct the issues that cause premature wear. This guide will help you troubleshoot, repair, and ensure long-term reliability.

Dead Motor or Electrical Issue?

Not every “dead” headlight motor is truly bad.

• Use a meter to test for voltage at the motor terminals.

• If voltage is present but the motor doesn’t run, connect it directly to 12 volts from the battery.

• If it operates under direct power, the fault is likely in the C4’s wiring harness or headlight actuator control module, not the motor.

C4 Headlight Bucket Alignment

One of the most common causes of C4 headlight motor failure is a misaligned headlight bucket.

• With motors removed, manually rotate the buckets from closed to fully open.

• Movement should be smooth, without binding or hard spots.

• Many Corvettes have suffered minor front-end bumps, creating friction that stresses the motors.

• Correct alignment ensures the new motor isn’t fighting unnecessary resistance.

Switch & Actuator Control Module

Starting in 1988, the C4 Corvette moved from a failure-prone three-relay setup to a single headlight actuator control module.

• Listen for the motor attempting to engage when the switch is activated.

• If there’s no response, test both power and ground circuits.

• A faulty switch or control module (GM reference 16510537) is often the culprit when motors test good but don’t operate in the car.

Gear & Internal Wear

A spinning motor with no bucket movement usually points to stripped gears.

• If the motor runs continuously but the light doesn’t move, internal gears have failed.

• Replace the motor assembly or upgrade to a modern reproduction for smooth, factory-style function.

Because Details Matter

Corvette C4 headlights are more than a styling cue—they’re a mechanical handshake between driver and car. When the motors fail, it robs the Corvette of part of its character. By checking alignment, electrical connections, and gear integrity before installation, you protect your investment and ensure your Corvette’s headlights perform just as GM intended.

At Mid America Motorworks, we’re proud to help C4 owners preserve both function and authenticity with quality headlight motors, actuator kits, and control modules.