Silverado brakes locking up. - Page 2

Sonny01 · 08-07-2006, 12:25 PM

You can get to the sensor by removing a front tire. It's attached to the wheel hub and easy to get to. After you get it all cleaned up and reinstalled find where it plugs into and disconnect it (normally up in the engine compartment). Plug an AC volt meter into the sensor line...reinstall the tire and give it a spin while watching the meter. Anything under 350 is bad and you either need a new sensor or the rust has moved the sensor so far away from the ring inside the hub it can't get a good hit as it moves past it. Do the other side...if you get a good reading put that sensor on the bad side and spin it again. If the voltage is up then the original sensor is bad. If the good sensor is now bad you need a new hub or more rust removal...get a new hub. But first I'd contact Chevy and argue with them about your truck being a possible lawsuit down the road. Try the dealer first then Corporate GM.

Capt. Delta · 08-07-2006, 01:37 PM

You've been a big help Sonny. I took it to the dealer this morning. I handed them their own TSB and recall bulletins that I had downloaded from the net. They couldn't even find them on their own computer. Have you seen the commercial where the guy is working with a bunch of monkeys. I always wondered where that company was located. Now I know. They're looking at the truck as we speak.

We did have a serious "chat" about customer service and competent mechanics.

I assume when you said 350 that would be in milliamps or millivolts. Are there two wires on the electrical connector? One for each probe on the tester or just one wire (+) and the other to the body (-) If two, does it matter which one goes into which and this has to be an AC tester not a DC tester, right?

Hopefully I won't have to deal with it and they will make it right. Maybe I should bring them a shop towel to wipe the egg off their face.

Sonny01 · 08-07-2006, 02:59 PM

Capt. Delta...are you a pilot?
Here it is...I just found it...02-05-25-006A ABS Activation at Low Speeds (11/26/02).
350 AC Millivolts. HeHe I forgot to make it .350...I knew what I meant...I just didn't pass it along.
If you get the wires backward it will still works just fine...what won't work is to ground the - voltmeter lead and then try for a reading on the - wire from the sensor.

Capt. Delta · 08-07-2006, 09:28 PM

Sorry not a pilot. I'll send you a seperate E-mail message to explain Capt. Delta so as not to clutter the forum up.

Dealer called this evening and said the sensors are not bad. They're going to check a few more things in the morning and take it for a test drive. (DUH!!)

They asked if the problem started when I put the new slotted/drilled rotors on 2 weeks ago which it didn't. Just got more exagerrated. I can see where they are going to try and go with this. Lets see...ABS fuse in brakes lock up, ABS fuse out breaks work fine. I think even a chimp can figure that one out. But in fairness I guess they are exploring all possibilities. I've spent so much time at the dealer I'm going to have to add them to my Xmas list or some other more appropriate list.

Sonny01 · 08-07-2006, 10:10 PM

I have a complete set of Brembo slotted rotors and NAPA pads on my truck and with the exception of the front rotors needing to be turned...which you can't do...they are just fine and the system works the way Chevy intended it to, after everything has been upgraded or replaced of course. I bought a set of the cross drilled Brembo's to put on the front, which is what the factory (Brembo) says I should have bought in the first place. The entire brake system is weak if you ask me but once you buy the truck you have to make things work. I drove a friends Ford and about put everybody thru the windshield the first time I used the brakes...man they were nice. I'm still not going to buy one though.

Capt. Delta · 08-09-2006, 09:42 AM

VINDICATION!!!!!! Got a call from the dealer yesterday afternoon tellin me they had driven the truck 7 miles and no brake problems. ARRRRGH!!! I figure at that point they think I'm some crazy mutant. I told the service manager to take the car home with him that night and if no problems I'd pick it up this morning. Got a call at 7 AM. Said he drove it home with no problems. He lives "uphill" from the dealership. Going "downhill this morning the brakes started shaking violently. At least now they know I'm not a nut case. I also noticed the brakes would usually malfunction when I was going downhill and not applying the brakes. (Long slow freeway downgrades.) They also asked how long the truck has had a trailer brake controller. (Were on there when I got the truck 3 years/70,000 miles ago.)

They'll be calling the GM tech's today.

My question is: Has anybody ever had problems with a trailer brake controller activating the ABS?

Sonny01 · 08-09-2006, 10:41 AM

You don't by chance have a Prodigy brake controller do you? They have an internal device for controlling the brakes when you go up or down a grade so you don't have to futz with the controller setting. Going down it would activate the trailer brakes harder. I can't see how it could interfere with the truck brakes though.

Capt. Delta · 08-10-2006, 07:44 PM

Well here's the final from the dealer. They've had my truck for 3 days. Been in contact with the GM techs and they're all stumped. They disconnected the trailer brake controller and didn't cure the problem. Cleaned the speed sensors and no dice. Now they say it must be in the EBCM module and want $1200 to replace it. However they won't guarentee it will fix the problem. Hell if I'm going to spend $1200 on the "by guess and by golly" method. Only thing I can think of is to get one from a wrecking yard and put it on to see if it fixes the problem. I've also heard of places that will rebuild the unit. Anyone have experience with taking one off?

Sonny01 · 08-10-2006, 08:18 PM

Don't buy one from a wreaked truck...it might not work with your truck. Look back in this thread to 08-06-06 and I think I answered your question about taking the ECBM off. Before you do...call Gavin at ModuleMaster listed in my post...he'll get you fixed up.

gremlin96 · 08-10-2006, 09:30 PM

it took me kidnaping the service manager to get them to drive my truck till the problem started. my abs will start kicking in when the truck gets all nice and warmed up. normly around 40+ miles. thay would only diver the truck 1 mile 2 at the most.

drove to the next town and back then the abs started kicking in the manager told me i was not pushing on the brake enuff to fake it. till i stoped and told him well drive it. the first stop sign we came to the abs kicked in and we went right thru it. when we got back to the shop thay put the computer on it and said well there are no codes but we do have a problem some ware. come back when the abs light stays on.

Capt. Delta · 08-11-2006, 08:55 AM

Thanks Sonny. I guess I better start opening my AARP mail cause I'm gettin senile. Should have looked back through the threads. I'll be sending it off to ModuleMaster next week when I get time to take it off. I've seen other companies that will do it cheaper but it sounds like you've had good luck with them. Their web site certainly does a good job of selling their superior product. I'll let you know if it works but it will be a week or two.

Capt. Delta · 08-15-2006, 11:25 AM

"Sonny" Talked to Gavin at Modulemaster yesterday. Told him about the problem. He doesn't think its in the EBCM. Said he has heard of this on rare occassions where there is an intermittant break in the wiring. Usually in the harness where it goes between the frame and the body. Very helpful gentleman to talk to. Said it is probably the yellow/black wire that comes off the module. Went ahead and sent him the module to have it tested first. Last thing I want to do is start breaking into the spaghetti of wires looking for a break. Said there's no charge for testing the unit. Sent him a check anyway. Think I'll go ahead and upgrade it as long as he's got it even if sez working fine.

Sonny01 · 08-15-2006, 03:57 PM

It's a good idea to upgrade the ECBM...plus...now you can drive and if the brakes act up again then it's not the ECBM or the ABS system. I'm glad you're making progress. I hope Gavin fixes the problem for you.

Capt. Delta · 08-27-2006, 10:51 AM

Arrrgh!!! Got the EBCM back from ModuleMaster. Put it in and the same problem. I did call but was not able to talk to Gavin. Their file did show a DTC of E265 (Open relay circuit) when it was brought in. I have to talk to Gavin and find out if that error code would have been caused by removing the fuse. If not I'll be tracing every damn wire from the EBCM. That will be a nightmare.

Sonny01 · 08-27-2006, 10:57 AM

Man...that's a tough one...I'm going to read thru all of your posts and see if I'm missing something.

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