Tail lights are a safety feature on every car, truck, and SUV. These lights make it easy for drivers behind you to see where you’re going and how fast you’re going.
They also warn other drivers that you’re braking, signaling a turn, or slowing down to stop at a red light or stop sign. The brake lights let other drivers know when you’re slowing down or stopping — especially helpful when the weather conditions are poor and visibility is low.
The tail lights in your car won’t turn off? Join the club — this seems to be a frequent problem. We’ll tell you why it happens and how to fix it.
Why don’t my tail lights turn off?
Your car has a relay switch that controls the current running through your headlights and brake lights, so they stay on as long as there is power going through them.
The relay switches only have an “on” position, so there’s no way for them to know when you’re using your brakes or turning on your headlamps so they can automatically turn them off.
On most cars, you’ll have to take the cover off the relay, and manually flip the lever that connects to the brake lights and headlight wires. Each car is different, so check your owner’s manual if you’re not sure where the relay is or how to fix it.
If your car’s taillights are staying on when you turn the car off, it’s probably because your headlamps or brake lights are stuck on. This is a common problem in older cars, but there are a few things you can do to fix it
Why do my LED tail lights stay on?
If your car has LED tail lights instead of regular bulbs, it’s possible that you’ll have this same problem. The problem is the same — the LEDs are getting stuck in an “on” position.
The fix for your LED tail lights is almost exactly the same as for regular tail lights. Check the fuses and make sure your relay is still working properly.
If you’ve already checked the fuses and the power wires, it’s possible that your headlight and brake light switch is at fault. This is located on the foot pedal or steering column, depending on your car model. Look for a black box with wires attached to it.
What do you do if your car Tail lights won’t turn off?
Fix No. 1: Check the fuses
Old cars have a lot of exposed wires and fuses, so if you were parked in the sun or near a heat source like an engine or heater for extended periods of time, the wires can lose their insulation and cause unnecessary power loss in your lights.
Check your owner’s manual to see where your fuse box is located on your car and test all the fuses to make sure they’re still working. If one of your bulbs isn’t working at all, replace the fuse with another from your package before you go out and buy one new one.
Fix No. 2: Get a new relay
Even if you’re not aware of it, there’s a good chance that the relay in your car has gotten old and the switch is fading out. To check this, take your car off the road and put it in neutral.
Make sure the engine is off and all of your lights are on. Now try to manually flip the lever that connects to your brake lights and headlight wires. If you can’t flip it or if it’s really difficult to move, your relay is probably getting old and needs to be replaced.
Fix No. 3: Check your headlight and brake light switch
If you’ve already checked the fuses and the power wires, it’s possible that your headlight and brake light switch is at fault. This is located on the foot pedal or steering column, depending on your car model.
Look for a black box with wires attached to it. If you have trouble locating this box, check out our guide to finding the ignition switch on your car. Once you’ve found this box, test each wire connected to it. If one of them isn’t working properly, you’ll need to replace that wire.
Follow the steps above to troubleshoot your tail lights. If all of these fixes don’t work and you can’t find a bad wire, it’s possible you have a blown fuse or damaged wiring somewhere in the back of your car.
If this is the case, it’s best to get your car fixed by a professional. If you’re not comfortable doing any of this work yourself, bring your car into an auto mechanic.
He or she will be able to test all your wiring for shorts or breaks and do any necessary repairs to make sure your tail lights are working properly. Remember: If you can’t turn off your tail lights manually after checking the fuses, it’s probably a problem with those wires in the back.
Robert Anderson is a world class motorhead who rebuilt his first carb at age 10, his first engine at age 15, and completed his first full hotrod build when he was just 18! Previously, he has ran a part warehouse, delivered pizzas, and managed the service department for a $20 million/year revenue dealership. Robert knows cars like few others and he is passionate about sharing his knowledge.