ABS Problem

[95 Cutlass Drop Top]

ABS light and Brake light on at the same time. If I hold the brake while im starting the car both lights will go out, but soon as i let go, right back on. When I let go I do hear the ABS motor make noise then the lights come on. Does anyone know my problem ? I've also checked fuses

[Slade901]

I've read some thread before that once the alternator is dying, one of the devices that the computer disables is the ABS.

 

Once the engine is running, does the ABS and Brake light turn OFF when you press the brake pedal OR the ABS and Brake light stays ON? The problem could be the brake pedal switch going bad. Check the ABS sensors on the wheels, try cleaning it as it may have magnetic particles covering/blocking the ABS wheel speed sensor.

 

I would disconnect the battery for 15 minutes to try to reset the error code and see what happens.

[95 Cutlass Drop Top]

I doubt its the alternator it pretty new. The light stays on all the time, the only time it goes off is when im holding the brake while im starting the car, but when i let go back on. I've tried to dissconnect the battery but i haven't tried to clean the sensors

[runt]

Are you low on fluid? Don't know if that would throw a ABS light, but could throw a brake light.

 

My guess would be wheel speed sensor.

[95DropTop]

While I was test driving my convertible, both lights came on and stayed on like what you describe. Problem: ABS module had a problem. IT seems that one of the gears in the ABS system (mounted under the master cylinder as one whole *translated EXPENSIVE unit) had dropped out and was causing the problem. The dealership replaced the entire unit - something about not being able to line up the gears once the unit had turned with the one gear dropped out. Cost to me: $0, I checked on ebay and the unit was over 600 bones!!! Oh, and I went to the shop where the unit was replaced and made sure they had the old one sitting on the counter! Hate to be told one thing and it turn out to be a fuse or they just reset the code. No problems almost a year later. As far as any symptoms, there were none. The car seemed to handle and brake normally. I did not try any hard braking to test the anti lock - I just assumed it would not function properly.

 

I also suffered from the alternator burn out causing the ABS light to come on while driving. It would not stay on all the time - usually when the RPM's rose, the alt put out enough to provide power to the ABS. Problem is when the power is not up to normal, the first thing that kicks out is the ABS as it takes a lot of power to keep it working. Again, no perceptible problems aside from the light.

 

I am not sure how to determine if the ABS is bad, but that is what mine did - perhaps some one can provide the code(s).

 

Good luck and keep us posted.

 

Thomas

[Cuhlass3100]

Thats the same thing that my 95 cutlass was doing last year. I took it to someone that specialized in GM cars since no one else could figure out what was wrong. And it turned out that a nut came loose inside the master cylinder and caused the back brakes to not work.

 

But most importantly I would find someone with a tech 1 because even though shops told me they could fix it, without the tech 1 they could not do anything the car.

 

The sound you hear is the unit clycling itself, when you put your foot on the brake when you start the car it will not do it and will attempt to do it when you take your foot off of the brake.

I hope this helps you out.