brake & abs lights on after tran fluid flush and change

[SSGUY]

Sorry if this was brought up before, im new here and didnt see it..

My brake and abs lights just came on.
Had my tran "flushed" and new fluid and filter added last week. (not done at dealer)
65000 miles on 2000 silverado 2wh dr 5.3.

I did read where there are sensors that may be at fault here.. but not sure what, where, or how to check..
Hate to take to a dealer if i dont have to..
Can take it back where it was done but figured id check here first.

Thanks in advance for your expertise.

[Sonny01]

Originally Posted by SSGUY

My brake and abs lights just came on.
Had my tran "flushed" and new fluid and filter added last week. (not done at dealer)

I don't think that the above service is your problem since it's two completely different systems...do a search in this forum on ABS and you will find a wealth of info. Or, contact Module Masters at:
http://www.modulemaster.com/en/index.php
Just by going to their website you can learn a lot. I had the ABS system go out on my 2000 EXT Cab 5.3 twice and both times Module Masters saved me tons of money over the dealer.

[SSGUY]

Thanks Sonny ill do that. Dont want to waste time going down the wrong road..

[SSGUY]

Hey Sonny, 3 more things:
1) i forgot to mention that i went over a curb and hit the frame right around the abs unit but did not hit the unit.. would that have knocked out the ebcm although the brake/abs lights did not go on until a day after..

2) i went to module masters and saw where the unit is located on the frame rail, whats the best way to remove it? Do i need to unbolt the unit (entire pump)from the frame rail in order to get at the bolts that hold the EBCM to the abs pump? Hopefully not.
(I just crawled under didnt jack it up or anything to take a quick peek)

3) They did not say how much the module would be to fix any ideas on that?
They did mention insurance should be for around $700. so thinking that is approx to what it will cost.
Thanks.

[wafrederick]

First thing to do is get it scanned for codes.Check your master cylinder if it is full of brake fluid also,a low master cylinder will set off the ABS light and this is true.

[SSGUY]

fluid is ok..
FYI I went out this am and wiggled a few wires around to make sure they were plugged in and all seemed ok..
took it for a ride and lights did not go on this time.. could i be lucky? or do you think it will come back? Ill answer that... Guess its hard to tell until i go for a longer ride.. just didnt know if this could be an intermittent problem or once it happens thats it... your stuck.. just wondering. thanks guys i appreciate your input..

[Sonny01]

The bad part is the placement of the EBCM which is on top of the ABS pump...it's held in with four steel torx bolts that face upwards and they rust. The first time the EBCM malfunctioned we had to take the pump off and cut off the bolts. I used the stainless steel bolts from Module Masters when I replaced it. The second time a torx bolt stripped out because when the SS bolts were put in I don't think the special anti-seize compound was used so off came the pump again. Once you get the EBCM off the pump and the pump is on the truck you don't need the EBCM for normal brakes...I don't advise driving this way but you can wrap the pump with plastic and have normal braking until the EBCM comes back from repair.
The pump has wires that corrode so I got a rebuilt pump from Module Masters also the first time.
I think the insurance $700 price was if it was lost in shipping what the factory price would be to replace it. I paid $140 about three years ago but it's probably more now.
And you need to have the brakes bled after taking off the pump, the best way is with a scanner.

[SSGUY]

This is sounding like a big pain in the a$$, im hoping the lights dont come back on. (but we probably know better dont we)
Glad the price is more like $140 than $700 though thats always a good thing.
I'll let you know how it goes. appreciate it guys.

[SSGUY]

well the brake/abs warning lights comes and goes. Taking it in to read the codes, hopefully they can read the codes even if the lights not on at that time.. seems to go back on after going over some bumps.

[SSGUY]

Took the truck in to get the codes read..There is a bulletin on this from GM and here is what it said:

"ABS Light ON, DTCS C0265, C0201, U1041 SET AND/OR LOSS OF COMMUNICATION WITH BRAKE MODULE (REGROUND EBCM GROUND)"
Ref# 04-05-25-002A Date: April 22, 2004 this is a revised bulletin, disreguard #04-05-250002 (sec 05 brakes).

It says the CORRECTION from one bullitin to the REVISED is this:
"DO NOT REPLACE THE BRAKE MODULE"

Perform the following steps to improve the connection of the ebcm ground:
1) Remove the ebcm ground. The ebcm ground is located on the frame beneath the drivers side door. If multiple grounds are found in this location, the ebcm ground can be id'd as the heavy 12 guage wire.
2) clean the area front and back using a whiz wheel.
3) Install the bolt, ground and a star washer to the frame.
4) install a star washer and nut to the backside of the frame. tighten the nut to 9n.m or 79 lbs in.
5) cover the front and back side of the repair area using rubberized undercoating.

I had this done and so far it has worked.
Cost me $65.00

So far im a happy camper.
Will update if the problem comes back.
Thanks everyone for your help and information.

[Sonny01]

Wow...I've never heard of that bulletin...thanks for up-dating the forum with the fix.
Sonny01

[SSGUY]

No problem Sonny, i appreciate you trying to help me out and for your information..