99 Grand Am Se - "ABS" and "Brake" lights [Archive] - GrandAmGT.com Forum

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blasfemaz
09-25-2009, 01:10 PM
Hello my fellow grand am lovers,

First I'd like to thank all the contributors for helping us all out with their guides. I am not new to the forums, but I've never actually registered before.

My car is a 1999 Grand Am SE.
I recently got it running again after having it sitting for around a year. I just didn't have the $800 dollars the dealer wanted to replace the ecm. Finally I found someone that programmed a used one to my vin and sold it to me for $60.
I actually had given up on my poor car, I didn't think anyone other than the dealer could provide the part.

Well anyway, thanks to several guides you guys have, I've been able to fix a couple of things myself. But now I am running into another problem.

The ABS light and the Breaks light are on all the time. As soon as I turn it on, they'll come on and stay on. Also my breaks pedal feels real hard, and when I break it will do it slowly. I'll press the pedal hard, but instead of immediately breaking, it does it slowly as if I were gradually pressing the pedal.

I would like to take it to the dealer for diagnosis, but I really do not trust the the one in my town. They lied to me telling me it was not possible to flash a used computer, and the only way was to buy their new one.
The only other option I have is to toe my car 90 miles away to the closest town with a dealer.

I thought perhaps someone here has experienced and solved a similar problem. Please point me in the right direction if you can.

Thank you,
Blas

AaronGTR
09-25-2009, 04:18 PM
Wow... they really told you $800 for a new PCM? That's the technical term btw, Powertrain Control Module. :) That's a scary high price. Even a new pcm from gmpartsdirect is only about $200 and installing and flashing it is only a 10-15min process.

Well anyway, ABS and brake light is usually an issue with a wheel speed sensor, but the traction control light usually goes off with that as well. That along with the brake pedal issue you are having sounds to me like it's probably something else. Very hard to say what without seeing the car, but it might be related to the car sitting for so long. Perhaps something got rusted on the brakes and isn't moving freely? Or maybe their is moisture in the brake fluid itself and something in the ABS unit got rusted? It would definitely help to find out the code that is set. The ABS computer will set a code that will be stored in the BCM. Unfortunately a normal scanner/tuner will only read the PCM. You need someone with a tech2 or other high end auto shop scanner capable or interfacing with the BCM. It will also probably require a more thorough tear down/investigation to diagnose the problem. If you aren't comfortable getting that in depth in the brake system I'd say try taking it to that other dealership. Is there any kind of regular mechanics shop by you? Some shops aren't as good as the dealerships, but sometimes they are just as good but cheaper and won't BS you about the price or what needs to be fixed. It depends on the mechanic, but some good mechanics do business that way in order to gain customer loyalty and get people to come to them instead of the dealer because they know they can be trusted. Ask around and see if anyone can recommend you to a good shop. ;)

2000 GT Coupe
09-25-2009, 07:43 PM
I was having that problem and it turned out to be a bad ground wire.
It took a lot of time to find it though.

blasfemaz
09-28-2009, 08:12 AM
Thanks for all the advice. It's true, the dealer here wants blood. I am mostly mad at myself for being so gullible, I stopped trying to fix my car.

You know I thought about it, and now that I remember, I actually had this problem since before my car was sitting. So that may rule out the rusting theory.
I am sorry, I forgot to mention that the traction control light does come on and off randomly.

I will try to see if I can find a mechanic with that scanner. The problem is I am in a really small town. There is not much here, and I am afraid taking it to a dealer outside town is too difficult for me right now.

2000 GT Coupe: Would you be willing to share a little more detail on how you resolved your problem?

Thanks

2000 GT Coupe
09-28-2009, 11:32 AM
Thanks for all the advice. It's true, the dealer here wants blood. I am mostly mad at myself for being so gullible, I stopped trying to fix my car.

You know I thought about it, and now that I remember, I actually had this problem since before my car was sitting. So that may rule out the rusting theory.
I am sorry, I forgot to mention that the traction control light does come on and off randomly.

I will try to see if I can find a mechanic with that scanner. The problem is I am in a really small town. There is not much here, and I am afraid taking it to a dealer outside town is too difficult for me right now.

2000 GT Coupe: Would you be willing to share a little more detail on how you resolved your problem?

Thanks
Sure, as to a scanner do you have a laptop? I bought a program http://www.obd-2.com/ $122, for a single type or $149 for 2 types and I think $240 for everything.

I used that as a start point it will read the abs module, in my case though the connection was intermittent which told me loose connection. After lots of trial and error I noticed that when it rained it would get a connection, that hinted at ground wires. I sprayed my engine bay with a hose one section at a time till I found a place that made the connection work. Then I looked for wiring and I found a large bundle ground point, Right near the trans fill hole. I pulled the bolt out and took some emery cloth and cleaned up the connector the bolt hole and the bolt head. Took care of the problem.

blasfemaz
09-30-2009, 03:56 PM
Sure, as to a scanner do you have a laptop? I bought a program http://www.obd-2.com/ $122, for a single type or $149 for 2 types and I think $240 for everything.

I used that as a start point it will read the abs module, in my case though the connection was intermittent which told me loose connection. After lots of trial and error I noticed that when it rained it would get a connection, that hinted at ground wires. I sprayed my engine bay with a hose one section at a time till I found a place that made the connection work. Then I looked for wiring and I found a large bundle ground point, Right near the trans fill hole. I pulled the bolt out and took some emery cloth and cleaned up the connector the bolt hole and the bolt head. Took care of the problem.

Thanks for sharing that. Sadly I cant afford to buy the scanner at the moment. I tried calling the 3 popular auto repair shops in my town, and none of them have that tech2 scanner to check the bcm. All of them told me only the dealer can help me. So that sucks...

Y2KGA
09-30-2009, 06:49 PM
I purchased an USB OBD cable off ebay for 30 dollars to use with my laptop. It took some research but I was able to get it to extract the code that was stored in the abs computer. I downloaded an fully functional OBD demo software (www.glmsoftware.com) that has a terminal window. Most basic OBD software communicates with the PCM only. The terminal software allows you to redirect the scanner so that it talks to the ABS computer. You get back raw numbers but they aren't hard to translate. You would then need to find out what the codes mean. Let me know if you want more info.


Thanks for sharing that. Sadly I cant afford to buy the scanner at the moment. I tried calling the 3 popular auto repair shops in my town, and none of them have that tech2 scanner to check the bcm. All of them told me only the dealer can help me. So that sucks...

squalidjoker_mx
05-08-2012, 07:17 PM
I am having the same problem now. Would you mind sharing what was the outcome?

Malaclypse
05-08-2012, 07:43 PM
If the dealership was talking about the EBCM as opposed to the ECM... then $800 sounds about right.

Those ABS modules get up there, unfortunately.