Brake warning lights coming on

[withac]

Okay, so I disconnected my battery for a good 10 or 20 minutes then hooked it back up. I drove downtown to run some errands and when I started the ‘** the Brake and ABS lights were lit solid. After I shut the ride down and started up again the lights were out. I figured it would have set a code so I drove to my mechanics and had him plug his code reader in. NOTHING, NADA, ZIP. So now the plan is next time it happens I’ll call him and if he’s in run over and have him check while the warning lights are lit. Any other ideas?

 

[LazyAssLou]

When my abs and brake lights come on, it also displays "service brake system" and then dings for about 15-20 seconds. Might be different on mine being an 03 model.

Same exact thing happens to me but only when I activate my fog lights. I am not sure what the heck it is! I just stop using my fog lights.

But then again, my truck was stolen in March and it only started doing this after I got my truck back.

 

[Chucktown Mako]

Same thing with my Stepfather's '01 Sierra. Lights were coming on before, but as soon as we took it to the shop, none lit up. Definitely go by when they are on. After reading info from the web site in my last post, it doesn't look like you are going to hurt anything by driving it, and you can disconnect the whole damn thing and still drive. My questions now is, what the hell is the point in the module anyway? Dealer made me believe that it was something serious, not to be ignored.
Latest shop says there is no "history" code or something,even that can tell them what it was doing.

LazyAss: I would think your problem is a short somewhere, with the whole fog light issue. Rip into your dash and see if any bare wires are touching.


Good luck fellas. Let us know how it turns out!!

 

[withac]

Same thing with my Stepfather's '01 Sierra. Lights were coming on before, but as soon as we took it to the shop, none lit up. Definitely go by when they are on. After reading info from the web site in my last post, it doesn't look like you are going to hurt anything by driving it, and you can disconnect the whole damn thing and still drive. My questions now is, what the hell is the point in the module anyway? Dealer made me believe that it was something serious, not to be ignored.
Latest shop says there is no "history" code or something,even that can tell them what it was doing.

LazyAss: I would think your problem is a short somewhere, with the whole fog light issue. Rip into your dash and see if any bare wires are touching.


Good luck fellas. Let us know how it turns out!!

I would assume without it you just have no ABS, it's still driveable, normal braking still works, just no anti-locks like the old days.

 

[nmsyukon]

Got a code C0265. I guess I will try this tomorrow:

"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.

 

[withac]

Got a code C0265. I guess I will try this tomorrow:

"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.

So in simplified terms, find the ground from the ecbm and make sure is has a clean, solid contact. What would you spray on it if you didn't have rubberized undercoating? I just crawled under and looked. It's hard to tell without having it on ramps to see better but I couldn't see a ground, all I could see was a real big wire bundle coming out and heading to the front of the truck.

 

[nmsyukon]

Just looked under mine tonite and I didn't see the ground wire either. Maybe in the daylight and up in the air I will be able to see better, but no luck tonite. The bulletin made it sound easy.

 

[DanS]

alot of great info thanks guys

 

[firewalkeravl]

I had an 01 Tahoe that had this same problem. They only thing that fixed it was to replace the EBCM, however I went to Mieneke locally and got one from a salvage supply with really low miles and never had the problem again. Sold it about a year later to a friend who has never had a problem either. It only cost me $280 including parts and labor. I was told a new one aftermarket is about $380 plus labor.
I NEVER EVER EVER go to the stealership. Bunch of god dammed thieves in every sense of the way!

Almost forgot; these guys will repair them.
https://www.absfixer.com/
If I remember right it' about $150 to repair, they seem legit, maybe someone can chime in.

 

[01TX_Tahoe]

I'll have to look at mine and check the ground wires...if I can find em. Might have to make a trip out to the local junk yard too.