Skip the auto shop - Our mechanics make house calls

Q: Brake lights not working in a 2002 Chevrolet Trailblazer

asked by on

The brake lights on my SUV aren't working, but the one in the middle does. All the other lights are working fine. I checked fuse 12 and 34, and those are fine. The bulbs are still good. I did some research, and there is a brake switch located on the brake pedal. Is that linked to the brake lights directly? Is it possible for the switch to go bad? Anything else that might cause my main brake lights not to work?

A: Looking at the wiring diagram for your vehi...

Looking at the wiring diagram for your vehicle, I see that all the brake lights share a common ground. They also all utilize the brake lamp switch, so both of these items can be ruled out. The only thing the third brake light does not share with the other brake lights is the #16 vehicle CHMSL fuse. Since you said the third brake light bulb is good, I would check this fuse. If there isn’t a problem with the fuse, then there is a problem with the third brake light wiring. Electrical diagnosis can be difficult, so I suggest you have a trained professional inspect your vehicle’s brake light problem firsthand.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car won't start after overheating

Serious damage can occur when a vehicle is allowed to overheat. A good first step would be to have a compression test performed by a qualified technician to ensure that the combustion chamber's cylinders are receiving compression. Overheating can cause...

Q: Follow up to possible ABS wheel speed sensor issues

Hi, thanks for writing in. If you just had the brake pads replaced and did not replace or resurface the rotors, then the brake pads are going to take longer to seat into the rotors. This could cause one brake...

Q: How do I use the turn signals?

Turn signals are very important safety features. The turn signal lights allow surrounding drivers to know that you are going to make a turn, which is an important safety precaution. Failing to use your turn signals is also illegal. Using...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.