1. Brake Light Switch: This is the most frequent cause. The switch is located near the brake pedal and activates when you press the pedal. It's a relatively inexpensive and easy part to replace. A bad switch might not make proper contact or might be internally broken.
2. Bulbs: Check the brake light bulbs themselves. They might be burned out, even if the tail lights/running lights work.
3. Fuses: Examine your fuse box for blown fuses related to the brake lights. The owner's manual will show you the fuse layout and which fuses are for the brake lights.
4. Wiring: This is the most complex issue. A break in the wiring harness between the brake light switch and the tail lights is possible. Corrosion, damage from rodents, or a poor connection at a connector are all potential causes. This requires tracing the wires.
5. Brake Light Circuit Board (if applicable): Some vehicles from this era had circuit boards involved in lighting. A faulty component on such a board could be the problem. This is less likely than the other issues.
6. Relay (if applicable): While less common in simpler systems like an '84 Corvette, a dedicated relay for the brake lights might be failing.
7. Ground: A poor ground connection somewhere in the brake light circuit can prevent the lights from functioning. Check the ground wires for corrosion or loose connections.
Troubleshooting Steps:
1. Check the Bulbs: The easiest and quickest check.
2. Check the Fuses: Look for blown fuses as indicated in your owner's manual.
3. Test the Brake Light Switch: You can do this with a multimeter (if you have one) to check continuity when the brake pedal is depressed. If you don't have a multimeter, a helper can press the brake pedal while you visually inspect the switch for movement.
4. Inspect the Wiring: Carefully inspect the wiring harness for any visible damage, breaks, or corrosion, particularly near the brake light switch and the tail lights.
If you are not comfortable working with car electrical systems, it's best to take your Corvette to a qualified mechanic. Improperly working on the electrical system can lead to further damage or even injury.
