Abs Light

olecarman · February 24, 2011

O.K.. I know and have read some of the post about ABS warning light. And one of the post said to check and clean the connections to the PMV assembly. My question is where is the PMV assembly on my truck located ? I have a 2001 GMC Seirra 2500 4X4. I have a similar situation to many, that my ABS and Brake warning lights come on sparatically. It is definately affected by warmer temperatures. It will not come on when the truck is cold and just heading out. But after driving for 15 minutes or so, and the outside temperature gets warmer, then the lights may come on, but it is so unpredictable. It typically won't come on at all if it is cold outside. I went to trade the truck last week on a newer model, and the sales guy wanted to take it for a drive, and guess what came on !! Yeah, the ABS and Brake lights when he started it up. OUCH !! Hurt my trade in value for sure, but I didn't deal anyway. I can cut the switch off and back on and it may go out and you not see it for days. Then again, it may come right back on. But it definately will not come on when the truck is cold and you first start it up. You have to drive it for a while before it comes on. I have driven for days and it not come on, then it might come on every other day !! But it "always" goes off after it sits and is cold. Any other thoughts?

I guess I need to take it to the dealer to check the codes.

Thanks,

KLB

8.1HD/ALLISON · February 24, 2011

The BPMV is located on the drivers side frame rail under the cab. It has all the brake lines going in it. I know there was a bullitin about cleaning a ground for some stuff. This might be on of them. Can't remember. Go down to the frame on the drivers side, at the front of the door where the front cab mount is and you will see about 2 or 3 ground wires. Remove the bolts, clean the wire terminals, bolts, and frame and reinstall. That might help.

zachary00 · February 24, 2011

I am having the same problem, but temperature isn't a factor. Just goes on and off sporadically. I do loose ABS when the light is on, but regular breaking is fine. Mine is an '05 2500hd 4x4.

sahls01gmc · February 24, 2011

I have the exact same truck as the OP, and the exact same problem!!! Thanks for the tip 8.1, I'll check that out.

Also, are the 2 metal brake lines on the left rear the parking brake? They seem to rub where they somewhat cross over eachother, is this normal? If not, could this also be an issue?

James

zachary00 · February 25, 2011

O.K.. I know and have read some of the post about ABS warning light. And one of the post said to check and clean the connections to the PMV assembly. My question is where is the PMV assembly on my truck located ? I have a 2001 GMC Seirra 2500 4X4. I have a similar situation to many, that my ABS and Brake warning lights come on sparatically. It is definately affected by warmer temperatures. It will not come on when the truck is cold and just heading out. But after driving for 15 minutes or so, and the outside temperature gets warmer, then the lights may come on, but it is so unpredictable. It typically won't come on at all if it is cold outside. I went to trade the truck last week on a newer model, and the sales guy wanted to take it for a drive, and guess what came on !! Yeah, the ABS and Brake lights when he started it up. OUCH !! Hurt my trade in value for sure, but I didn't deal anyway. I can cut the switch off and back on and it may go out and you not see it for days. Then again, it may come right back on. But it definately will not come on when the truck is cold and you first start it up. You have to drive it for a while before it comes on. I have driven for days and it not come on, then it might come on every other day !! But it "always" goes off after it sits and is cold. Any other thoughts?
I guess I need to take it to the dealer to check the codes.

Thanks,

KLB

Did you have any luck with the fix? I tried mine to no success. Please let me know if you get a fix. This is driving me crazy, almost to the point of going to the dealership.

SENDRA · February 25, 2011

I have a 2001 Silverado that had the ABS light come on. At first it was intermittent and then it became constant. When the light was on I did not have ABS brakes.

It turned out to be my ABS module. It was located on the drivers side on the inside of the frame. I replaced it and it fixed the problem.

here is a link to a place that rebuilds them.

http://www.modulemaster.com/en/index.php

You can drive your truck with out that part on it and you just won't have ABS brakes. Just make sure to cover up the area with some foil and tape. I wouldn't drive anymore than neccesary, and I wouldn't be taking my truck off road while waiting for the part to arrive.

I hope this helps.

[email protected] · February 25, 2011

Same problem with mine, I unplugged the ebcm and took the cluster apart and put e-tape under the faceplate but over the abs light and no problems here.

sierrahi · February 26, 2011

Some cheap fuktard taped over the ABS light inside the cluster on my truck, and broke the L.E.D. for the tow/haul idicator while doing it. I found the tape while fixing the L.E.D. tow/haul indicator. I don't think its a good idea to hide those types of issues.