Third Brake Light Not Working (Quick Fix Guide):
Your third brake light can sometimes decide to take an unexpected leave. This can be a frustrating experience especially if you have no idea why it goes out. Luckily, this article will share helpful info on why your 3rd brake light is not working and how to restore its functionality.
Third brake light not working can be attributed to several potential causes including a burned-out bulb, faulty bulb socket, blown fuse, and wiring problems. A bad brake light switch or faulty third brake light housing can also stop this light from working.
In the following article, we’ll take a closer look at all the potential causes behind your center high-mount stop lamp malfunctioning. We’ll also share with you step-by-step instructions on how to troubleshoot and resolve this problem.
Why Your Third Brake Light Is Not Working
The third brake light not working while the primary brake lights still work can be caused by any of the issues discussed below:
- Burned-out bulb: One of the reasons your third brake light is not working could be due to a burned-out bulb. As you may already know, your auto bulbs don’t last forever. They will wear and eventually die with continued use. The good news is that all you have to do to fix this issue is replace the blown bulb with a new one.
- Bad fuse: In most vehicles, a separate fuse is used for the third brake light. The fuse simply protects the electrical system from an overload. If this fuse blows, it will definitely cut off power supply to the third brake light, causing it to stop working.
- Wiring problems: Another reason your 3rd brake light may be out is due to faulty wiring connecting your 3rd brake light to your vehicle’s electrical system. The wiring may be damaged, worn, frayed, corroded, loosely connected, etc. In some cases, the wiring may be completely disconnected.
- Bad socket/connector: Corroded sockets and bent/broken connector pins could be another reason your brake lights are not functioning. Discoloration of the socket is a key indicator of bad socket. Checking the connectors using a multimeter will confirm if they are functional or not.
- Failing brake light switch: You may argue that a bad brake light switch usually affects all the brake lights. While this is true, it is still worth inspecting it. This is especially true if you have ruled out all the other factors above.
Other potential culprits behind non-functional third brake light include bad ground connection and damaged third brake light assembly (this can let in moisture and other undesired elements that can affect the light functionality).
How Do You Fix Third Brake Light Not Working?
Below are some helpful troubleshooting tips for third brake light malfunctioning to help you fix this problem:
- Check if the 3rd brake light bulb is blown. If the bulb appears damaged or darkened, it’s blown and needs a replacement.
- If the bulb is alright, confirm if it’s the correct bulb for your brake light. Also, check that it’s correctly installed (you can even remove it and reinstall it to see if it works).
- Next, inspect the bulb socket for signs of discoloration/corrosion. Where necessary, use a wire brush to clean the corrosion.
- Do a continuity test for the fuse. If you don’t know the specific fuse for your brake light, run all the fuses through the test and replace the broken ones.
- Now examine the wiring connecting the stoplight to your car’s electrical system. Look out for signs of fraying or cuts or loose and corroded connections and repair/replace them as necessary.
- You can also test the wiring for continuity to help you find any broken circuit.
- Inspect all the connectors and connections for your brake light circuit and ensure they are secure and not disconnected.
- Test your brake light switch. If it is malfunctioning, replace it to see if the problem goes away.
Car electrical problems can sometimes prove challenging to diagnose. So, if you’re not comfortable doing the above diagnosis, don’t hesitate to consult your mechanic.
Also, if you have followed the steps above and haven’t fixed the issue, let a mechanic diagnose your car.
Where Is The Fuse For 3rd Brake Light
The fuse for 3rd brake light is usually located in the fuse box under your car dash, on driver’s side. But in some cars, the fuse is located in the engine compartment.
The exact location of this center high-mount stop light can vary depending on your car’s make and model.
That said, consulting your car owner’s manual will help you pinpoint the exact location of this specific fuse.
The fuse may be labeled “CHMSL” (stands for Center High-Mounted Stop Lamp), “Stoplight”, or something of the sort in different cars.
If you can’t pinpoint the fuse location, you can go the old-school way and test all the fuses in the fuse box for continuity and replace the blown ones.
Alternatively, you can consult a qualified auto technician or dealership for assistance in identifying this fuse.
How To Test The Third Brake Light
Follow the simple and quick steps below to confirm if your third brake light is functioning:
Step 1. Start your car by turning on the ignition. Ensure the engine is running so that power flows through the electrical system of your car for accurate test results.
Step 2. Now press your car brake pedal as you normally do while applying brakes. This should trigger the traditional and third brake lights to come on. Have someone stand at the rear of your car to observe if the light illuminates with the pedal action.
Step 3. If the brake light does not illuminate, then it indicates a potential issue. Further diagnosis is necessary to uncover the underlying issue so that your third stoplight can resume its normal functionality.
Can You Drive With Third Brake Light Not Working?
While you can still drive your car with the third brake light not working, we don’t recommend doing it.
As you may already know, this brake light serves as an additional safety feature in your car. It offers additional visibility to the drivers behind you, making it helpful in situations where the driver may miss your primary stoplights.
As such, driving with non-functioning third brake light can reduce your visibility regarding your braking intentions to the drivers behind you. And this increases the risk of getting rear-ended.
The third brake light is also a legal requirement in most states. If your light is out, you can be pulled over by a cop and given a citation or repair order.
A nonfunctioning 3rd brake light can stop your vehicle from passing state inspection if you reside in states that do car inspections more often.
With this in mind, it’s advisable to fix your third brake light issue as soon as possible and ensure it remains functional at all times.
How Do You Change A Rear Top Brake Light?
The exact procedure for changing your rear top brake light can vary depending on your vehicle’s make and model.
Below are the general steps to follow to replace your car 3rd brake light:
Step 1. Locate the 3rd brake light: This brake is usually located at the center of your car’s rear window, on the trunk lid, or on the roof of your car. Once you locate it, examine the assembly to determine how it’s attached to your car.
Step 2. Get the mounting screws off: Use a screwdriver to remove any mounting screws holding the assembly in place.
Step 3. Disconnect the bulb electrical connector: With the assembly out, now you need to disconnect the electrical connector powering the light. The process of detaching the connector can vary depending on the technique used to lock it in place in your car.
Step 4. Remove the blown bulb: Carefully get out the old bulb from its socket.
Step 5. Install the new bulb: Put the new bulb in place of the old bulb and ensure it sits properly and securely in place.
Step 6. Reconnect the connector back to the third brake light assembly. Still at it, you’d want to test if the light is working by pressing the brake pedal while someone observes if the light comes on.
Step 7. Reinstall the housing: If the light is working properly, reinstall the brake light housing back in place. Align the mounting holes and put back the screws you removed earlier.
How To Know If Your Third Brake Light Is Leaking?
As we hinted earlier on, a damaged third brake light assembly can also potentially cause your third brake light to malfunction.
In some worse cases, the assembly may be leaking and letting in water, which can cause damage.
If you suspect your light is leaking, look for key signs such as:
- Presence of moisture or condensation inside the brake light housings. This indicates that water is finding its way in and may affect the light if it has not already done so.
- Discoloration or rust signs around your third bake light housing are another sign of a leak
- If you’re experiencing issues uh as blown fuses, short-circuiting, etc., and you don’t know the cause, a leakage might be the most probable explanation.
- A damp or musty smell inside your third brake light housing could also be a sign of water getting through your stop light seal.
If you notice your brake light has a leak, be sure to fix it as soon as possible as it can make your brake light non-functional or even make it less visible to the drivers behind you.
If you’re facing the issue of your third brake light not working, it’s important to address the problem to ensure the safety of your vehicle. To learn more about this issue and possible solutions, we recommend reading our article on left turn signal and brake light not working on trailer. This resource provides insights into troubleshooting and resolving the issue. Additionally, if you’re curious about the legal requirements regarding brake lights, you may find our article on how many brake lights are required by law informative. It outlines the regulations surrounding the number and functionality of brake lights on vehicles.FAQs:
The most likely causes behind your Silverado 3rd brake light not working include burned-out bulb, blown fuse, wiring problems, or a defective brake light switch. A thorough inspection will help you determine the exact cause of this problem.
The third brake light is usually referred to as the center high-mounted stop lamp (abbreviated CHMSL).
The third brake light comes on when you press your car brake pedal, just like the traditional brake lights. It helps alert the drivers behind you when you’re slowing down or coming to a stop.
Conclusion
This article has just discussed all the common causes for a failing third brake light, including burned-out bulb, blown fuse, wiring issues, bad socket and connectors, grounding issues, and faulty brake light switch. Proper diagnosis is key to pinpointing the underlying issue and resolving it so that your brake light can start functioning again.
We have highlighted some helpful troubleshooting tips in the above article to help you easily uncover the issue behind the lights not working and resolve it. However, if you can’t seem to find out what causing the problem on your own, don’t hesitate to seek professional help from your mechanic.
