What fuse works the tail lights?
The tail lights are typically protected by a dedicated fuse in the vehicle’s fuse panel, usually labeled something like TAIL or TAIL/LT and often rated at 10 amps or 15 amps. Exact labeling and rating vary by make and model, so consult your owner’s manual or the fuse diagram on the fuse box cover to confirm the correct fuse for your car.
Where to find the tail-light fuse
To identify the correct fuse, you’ll need to locate the fuse boxes and read the diagrams that accompany them. The tail-light fuse can live in more than one location depending on the vehicle’s design, so checking multiple panels is common.
Common locations
Many cars place the main exterior-light fuses in interior panels (often under the dash on the driver’s side or in the glove compartment) and in the engine compartment fuse box. In some models, there is a separate rear or trunk fuse panel as well. Always use the diagram on the fuse box cover or in the owner's manual to pinpoint the exact location.
- Interior fuse box (driver’s side under dash, or in the glove box) labeled with TAIL or LAMP
- Engine compartment fuse box with a diagram showing TAIL, TAIL/LT, or LAMP circuits
- Rear fuse panel in the cargo area on certain wagons or SUVs
Consult the diagram on the specific fuse box cover and the vehicle’s manual, as some models combine tail-light functions with parking lights or other exterior lighting circuits.
Inspecting and replacing the tail-light fuse
The following steps guide you through identifying, inspecting, and replacing the tail-light fuse. This process is standard across most vehicles, though exact fuse labels may differ slightly.
Follow these steps to locate, inspect, and replace the tail-light fuse.
- Turn off the ignition and remove the key (and, if possible, disconnect the negative battery terminal before servicing electrical systems).
- Open the appropriate fuse box and locate the fuse labeled TAIL, TAIL/LT, or LAMP using the diagram.
- Carefully pull the fuse out with a fuse puller or needle-nose pliers to inspect it.
- Check the fuse for a blown element (a visible broken metal strip) or use a multimeter to test continuity. A blown fuse should read no continuity.
- Replace the fuse with a new one of identical amperage rating (commonly 10A or 15A; never exceed the labeled rating).
- Reinstall the fuse, restore power, and test the tail lights to confirm proper operation.
Replacing a fuse with the incorrect rating or bypassing a blown fuse can cause wiring damage or fire risks. If a new fuse blows again, there’s likely an underlying fault that requires diagnosis.
What to do if the fuse keeps blowing
If a new tail-light fuse blows soon after installation, the problem is likely a short, an overcurrent condition, or a faulty component in the circuit. Common culprits include a burned-out bulb, corroded sockets, damaged wiring, a faulty ground, or a problem in the body-control module (in modern vehicles). A professional diagnosis is recommended if the fuse continues to fail after replacement.
Other considerations when tail lights fail
A blown fuse is a common cause, but tail-light failure can stem from other issues. Systematically checking each part helps prevent repeated outages and ensures safety on the road.
- Burned-out bulbs or LEDs within the tail light assemblies
- Corrosion or poor ground connections at the tail-light housings
- Damaged wiring, broken connectors, or water intrusion into light assemblies
- Relays or body control module (if the vehicle uses electronic control for lighting)
- Possibility of a separate fuse for left and right tail lights on some models
If you’re unsure, consult the owner’s manual or a qualified technician. Modern vehicles may use networked control modules that can disable entire lighting circuits in fault conditions, which requires specialized diagnostic equipment.
Common fuse labels and rating Variations
Fuse labeling and amperage can vary widely by manufacturer. In practice you may encounter labels such as TAIL, TAIL/LT, LAMP, STOP/TL, or exterior-light groups. Ratings are typically 10A or 15A, but some vehicles use higher or lower values depending on the circuit design. When in doubt, always match the replacement fuse to the rating printed on the fuse itself and documented in the vehicle’s manual or fuse box diagram.
Summary
Tail-light fuses are usually found in the main fuse panels and are labeled to indicate their function, most often as TAIL or TAIL/LT with a 10A or 15A rating. To diagnose tail-light issues, locate the fuse using the diagram, inspect and replace it with the correct rating, and test the lights. If the fuse repeatedly blows, or if the lights fail even with a good fuse, inspect bulbs, sockets, wiring, grounds, and any control modules, and consider professional diagnostics for complex modern wiring systems.
If you can share your vehicle’s year, make, and model, I can point you to the exact fuse location and label for your specific car.
