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GM brake light failure advisory

I got a notice from GM today on my Pontiac G6. Just an advisory and not a recall. Problem is that brake lights can go on without the brake pedal being pushed or brake lights can go off when the pedal is pushed. The notice said don’t take it to the dealer unless you suspect this as a problem.

Not being too paranoid but will certainly pay more attention but my question is how in the world I can normally see whether the brake lights are intermittently on or not? Even the third light in mounted in the trunk wing so can’t see anything. I know at night I can see the reflection in back of me but otherwise, I’m at a loss without wiring a pilot light or something.

I don’t expect any answers.

Had a failing brake switch in our 03 windstar. The brake lights stuckon would kill the battery. Disassembly and wd 40 was my fix.

I sometimes park at a business that has a plate glass window facing the parking lot. When I’m there at night and parked facing the window I use the reflection in the window to check the headlights lo and hi beam, the parking lights, and the turn signals. It’s all done and tested in like 15 seconds that way. If I thought there was something amiss w/the rear lights I’d just park facing the other way & use the same technique. I think if there was a problem, this would eventually catch it.

I’m not surprised about that advisory

We have many brands in our fleet, GM and Ford probably the most common

And the GM brake lamp switches fail far more frequently, versus the Ford switches

Leave the garage door open and place your wife in a lawn chair to watch the car.

Well to be serious, the car doesn’t have to be in motion for the lights to be stuck on. If there should be a failure you would notice sooner or later.

you could always wait until a cop gives you a ticket for a non-working brake light.

1 Like

I don’t like the idea of no brake lights.
What I’d be tempted to do is to talk to some folks at a GM dealer or two (former Pontiac dealers) and find out what the exact culprit of these failures is. No doubt they’ve seen a few.

Then you could take the car in with a complaint of intermittent “backwards” brake lights and pay to have it fixed. Save the documents.

Then when this turns into a recall, GM will no doubt be reimbursing customers who had the problem taken care of, already. That’s how it usually goes down.

This beats a possible rear-end collision or a citation.

EDIT: Addition
If the dealer won’t fix it because they can’t replicate the problem then have them write their “No Problem Found” on the Repair Order. You can show it to the police or use it to go after GM for any damages if need be.

A G6 is just a poor man’s wanna-be Grand Prix! :smile_cat:

Sounds like if the cruise starts shutting off to check the brake lights. I can live with that. They made it a 15 year warranty.

That 15 years could become forever if it goes to Recall.


You are not being paranoid.

It looks like an electrical problem.

I would step on the brakes in a darkened area and see if they both light up.

Do so once a day for a week.

If the car is wired properly, the brake light will work consistently right.

Maybe a connection was poorly made(by the factory) and vibration makes it work sometimes and not other times.

Just my one cents.


Obviously my approach has some limitations, but every once in a while I will apply the brakes before I start the engine and before I open the garage door. The brake lights reflect fairly well on the metal garage door.

Many brake lamp switches aren’t as simple as you describe

They’re actually two switches, built into one housing

One part sends the signal to the brake lamps

The other part sends the signal to the control module(s) . . . they also need to know the brake pedal is being applied

It’s not uncommon for such a brake lamp switch to partially fail, meaning the brake lamps themselves function correctly, but the other part has failed

Yeah I do all that. m It’s evidently a fluctuating voltage problem developing over time. I’ll just have to pay more attention to it I guess.

Or a strand of fiber optic thread.