Imagine following the lead of someone who cannot give you any directions or maybe doesn’t even speak the same language as you.
Faulty brake lights work much in the same way for the drivers behind. Brake lights are meant to act as a guide for the tailing drivers, helping them position themselves on the road and preventing accidents, especially at night.
When your brake lights are not working but tail lights are, it could indicate several issues with your vehicle if the problem isn’t itself with the individual bulb.
This could be a smorgasbord of issues from faulty sensors, broken switches to chapped wires, and even electrical problems on the ground.
Daunting though this task may seem from above, finding the root cause of broken brake lights can be quite easy if you know what you’re looking for.
Since the brake lights and tail lights carry separate circuits for their operation, it’s quite easy to check for faults.
Sometimes, there are occasions where one of them works, and the other doesn’t. Why is that?
Why Are My Brake Lights Not Working But My Tail Lights Are?
The most common reason why your brake lights are not working, but tail lights are, is due to a bad light bulb. It can also be caused by a blown fuse, a bad brake light switch, or issues with the wiring.
Suppose your vehicle’s taillights are working fine, but the brake lights don’t come on when you press the brakes. Perhaps one light shines more than the other, or the taillights completely switch off when you press the brakes. These are strange problems to have because the connections for both lights come from the same source.
No matter what your problem, there is a reason for it, and there is a solution. Here is a more detailed list of why your brake light does not work but tail lights do:
#1. Bad Light Bulbs.
New cars often use LED lights for the taillights. But if you have an older car, you want to check the light bulbs.
The brake light and tail light often share the same bulb, but there are two different circuits inside it. This makes it possible that one circuit is functional, and the other one is burnt.
Replacing light bulbs is often very straightforward, and they are very cheap to replace. However, if you want to measure them to be sure they are not dead, you can measure them with a multimeter or use an external 12-volt source to test them.
That all three brake light bulbs have gone bad at the same time is pretty unlikely, but if you have been driving for a long time without noticing, it is absolutely possible. There could also be a circuit short somewhere that blew all the lights if the wrong fuse is installed.
If your brake lights are not working but the third brake light is, there is a high likelihood that the problem is just two blown bulbs.
#2. Bad Brake Light Switch.
Hydraulically operated, the brake lights turn over when the brake pressure sensor detects force applied on the pedal. In case the brake sensor is faulty, the relay of information will be inaccurate or completely hampered.
To assess the faulty brake sensor, you need to look closely for any delay in the activation of brake lights as well as lags in turning off as you take the foot off.
Alternatively, the brake sensor may be working fine but the switch might refuse to turn over the brake lights. In such a case you may find your brake lights not working despite the tail lights working fine.
The brake switch is located down the dash, where it connects to the wall, connecting to the pedal mechanism below.
If it is broken or loose, the brake lights will not work even though the taillights will turn on. To confirm if the switch is broken, try plugging the wires into another switch and if the brake lights do not turn up, you would need to get a replacement.
#3. Broken Fuse Or Fuse Box.
All electronic equipment in a car is supplied electricity through wires that go through a fuse box. Modern cars have two or more fuse boxes. There is often one below the dashboard, and there is one under the hood.
You need to take out your vehicle’s manual and find out your brake light fuse location. There is a high chance that, due to an electrical surge, the brake light fuse has blown. Identify the correct fuse and replace it with a similar one.
In most cases, there is a reason why a fuse is blown. If the fuse is blown, you should make sure that there is no circuit short on the wirings or in the connector to the brake light. However, in some cases, they can blow because they are old.
Remember to also check inside the fuse box for any signs of water, because water can cause circuit shorts in the fuse box, resulting in a blown fuse.
#4. Bad Sockets and Connectors.
Corrosion of the sockets or broken/bent connector pins can also cause the brake lights to stop working, though the sockets or connectors going wrong is not all that common.
If you have a broken brake light glass or the bulbs and sockets, have been exposed to moisture and rust in some other way, it could cause specific bulbs to not function.
Looking for any discoloration in the socket can help determine the fault with the brake lights while checking the connector pins using a multimeter can also provide definitive answers.
#5. Broken Wire.
All the sockets, switches, and sensors need a wired path to convey electricity and with a bevy of cables in the electrical system, it can be quite hard to find a damaged or shorted wire.
If you have checked the above components, potentially causing your brake lights to not work while not affecting your taillights, and found none of them at fault, there’s a good chance that the system operating those components itself is faltering.
The wiring is susceptible to a number of things from blights, insects, and corrosion to short circuits, so if you have tried all,
looking for chaps in wires can be helpful, although doing so for a regular person can be quite daunting,g if not just impossible. Having the wiring checked out by a mechanic is a better idea rather than going through it yourself.
What is the third brake light?
Colloquially known as the center brake light, the center high-mounted stop lamp present in many vehicles is a relatively new addition.
The two conventional brake lights on either side are meant to help drivers coming up close behind understand the position of your car with respect to them, So you might be wondering, what the third light on the rear is for, is it even necessary.
The center tail lamp unlike the normal brake lights serves a more thorough purpose. They help the drivers tailing far behind who might have both the right and left brake lights of their car blocked comprehend your position on the busy road.
This add-on in your lighting system is directly connected to the normal brake lights and shares the same circuit and ground. So all of the above ways you might use to check brake lights when they don’t function while the tail lights do are still applicable.
Why Should You Avoid Driving With Bad Brake Lights?
You can continue driving because your vehicle would still work, but that doesn’t mean that you should. Here’s why.
Increased Risk of Accidents
Without brake lights, drivers behind you can’t tell when you’re slowing or stopping. So if you brake abruptly, they might hit your vehicle. According to a study, rear-end collisions account for 29% of road accidents that led to serious injuries.
More Liability
The vehicle that’s at fault is liable in case of an accident. So if you crashed into a car because its brake lights aren’t working, then you might be able to file a compensation claim. Likewise, if you get rear-ended while driving with faulty brake lights, you could get in trouble with the law.
Legal Concerns
It’s illegal to drive with bad brake lights in some states. You can get pulled over by the authorities if yours isn’t working. You could get a ticket if more than one of your brake lights is faulty. Fines can vary depending on the state where you’re in.
Shift Lock Override
If your ride has a shift lock override, it would activate when it detects that one of your brake lights is out. It prevents the car from shifting once there’s a mechanic error detected. So you’ll risk damaging your transmission system if you continue to drive with bad brake lights.
How Much Does It Cost to Fix a Brake Light?
It depends on what’s causing the issue. For example, if you’re dealing with a bad brake light bulb, expect to shell out around $5 to $10 for a replacement. Mechanics might charge $10 to $20 for labor, depending on your vehicle’s make and model.
How can you tell if a brake light fuse is bad?
The best and easiest way to tell if the brake light fuse is bad is to remove the fuse and see if it’s melted or broken. If it is, then the fuse is bad. You can also measure it with a multimeter to be sure.
Driving around without brake lights is actually quite dangerous, because the cars behind you won’t see when you hit the brake pedal to slow down. Therefore, it is very important to fix the problem as soon as possible. Fortunately, this problem is often quite easy to fix.
The most common reasons why brake lights don’t work, but tail lights are working include:
- Bad Light Bulbs
- Bad Brake Light Switch
- Broken Fuse Or Fuse Box
- Bad Sockets and Connectors
- Broken Wire
As you can see, there are a few different things that could be going on if your brake lights don’t work but your tail lights do. It is important to diagnose the problem as soon as possible so that you can get it fixed and avoid getting pulled over or worse, causing an accident.
Electrical problems can be quite complicated to diagnose and solve without any special knowledge, so you may need to contact a mechanic specialized in car electronics and diagnostics if you have tried the simple things above.
Tail Lights Out, but Brake Lights Work?
What if your tail lights are out, but the brake lights activate? For the most part, you can follow the above steps as they relate to the tail lights, starting with checking your fuses.
Again, refer to your owner’s manual or find information online about which fuses correspond to your tail lights. If the fuses appear to be functioning normally, then you might want to check the bulbs — just make sure you are checking the tail lights and not the brake lights!
If you are unable to find the problem in either the fuses or bulbs for your tail lights, then this might indicate a wiring issue. Trying to trace a wiring problem through your vehicle is complicated regardless of make or model, so we strongly recommend bringing the vehicle to a professional mechanic at this point.
As with brake light issues, you’ll want to be careful driving without tail lights and avoid getting pulled over if at all possible.