1. Fuses:
* Locate the fuse box: This is usually under the hood or inside the car, often under the dash. Consult your owner's manual for the exact location.
* Identify the taillight fuse(s): The manual will show a fuse diagram. There might be separate fuses for the left and right taillights, or a single fuse for both.
* Check the fuses: Visually inspect the fuses for a blown filament (a broken wire inside the fuse). If you see a blown fuse, replace it with a fuse of the *same amperage*. Don't use a higher amperage fuse, as this could cause a fire. If the new fuse blows immediately, there's a short circuit somewhere in the wiring.
2. Bulbs:
* Access the taillight bulbs: This usually involves removing the taillight assemblies. Refer to your owner's manual for instructions.
* Check the bulbs: Examine the filaments in each bulb. If they're burnt out, replace them with new bulbs of the correct type and wattage.
3. Wiring and Connections:
* Inspect the wiring: Look for any damaged, frayed, or corroded wires leading to the taillights. Pay close attention to the connections at the bulb sockets and the main harness. A visual inspection might reveal broken wires or loose connections.
* Test the connections: Use a multimeter (if you have one) to check for continuity between the power source and the taillight bulbs. This requires some electrical knowledge. If you're not comfortable with this, skip this step and proceed to a professional.
* Check the ground: A poor ground connection can also prevent the taillights from working. Ensure the ground wire connected to the taillight assembly is clean and making good contact with the car's chassis.
4. Taillight Switch:
* Test the switch: This is more difficult to test without a multimeter. If all fuses and bulbs are good and the wiring seems okay, the taillight switch itself may be faulty. This requires more advanced diagnostics.
5. Tail Light Assembly Issues:
* Sometimes the problem lies within the taillight housing itself. Ensure the housing and associated connectors are securely attached. Corrosion in the socket can also cause intermittent operation.
If you're not comfortable working with car electrical systems, it's best to take your Fiero to a qualified mechanic. Improper electrical work can lead to further damage or even a fire. They have the tools and expertise to diagnose the problem accurately and safely.
