Hello:

This will be my first post here. Apologies if this information is already present somewhere on this site, as I could not find it after about an hour of searching so I decided to start this thread.

VEHICLE: 1996 GMC JIMMY, SLS 4X4 4.3L Vortec.
Basically here is the issue....

ABS light is "on" I had the stored codes read by my friend and his expensive scan tool at the local shop, 5 codes came back.

At this point I won't bother telling you the codes since I have decided NOT to try and repair the ABS system. My decision is final, deactivate it permanently.

According to my repair manual, the control unit for the ABS on 4WAL (4 wheel anti-lock) seems to be called the "Electro-Hydraulic Control Unit (EHCU) which I have already located. I have tried unplugging all of the wires attached to this EHCU and it seems to have no effect on the ABS system.

I have been trying to locate the EBCM on the vehicle with no success. The Haynes manual I am using is very vague on this topic for some reason and does not tell me anything useful about the EBCM or the location of the EBCM.

So my question is this.... Is the EBCM part of the EHCU? Or is the EBCM located somewhere else?? Will unplugging the EBCM deactivate the ABS system entirly, causing the ABS warning light in the dash to go out and leave me with good old power brakes?
At this point I just want to have my ABS light off, NO ABS, but still have regular brakes. What would be the easiest way to accomlpish this?

Thank you for your time!

 

Pull the ABS relay in the underhood fuse box and put a piece of electrical tape over the light on the dash. You'll need to pull the cluster out and remove the clear plastic.

 

Thanks, I will consider that, do you know where I can find the ABS relay by chance?

 

In the underhood fuse box. There's a diagram on the back of the cover that labels every fuse and relay. Not hard to find as long as you know how to read.

 

you could just pull the EBCM module and pull the bulb out of the cluster... its not too hard to do

 

yeah, no matter what you do the light will be on unless you pull the bulb out. You can either unplug the module or pull the fuse or relay. If you pull the fuse that will also deactivate your cruse control though.

 

really? mind telling me how on a '98+ cluster?

i was gonna start a thread on how to crack apart the cluster itself, but came across this thread (i'm wanting to disable that stupid ABS light in my cluster myself).

and when you refer to the "module", are you talking about the actual ABS pump/box (whatever you wanna call it) that's mounted up on the left inner fender well?

'cause i did that on my '92 (to disable the 4WAL system) and i never had any dash light issue.

mind you..........i haven't actually tried that on my '98 yet. fear there are too many systems interconnected in these damn trucks.

maybe i'll give it a shot, see what else might be affected. hope nothing is.

 

I'm wondering the same. I tried to pull the SES bulb in my cluster and had no luck.

 

I found this information on the 4WAL system used in GM's after some digging.... it was quite useful.

http://www.motor.com/magazine/pdfs/061998_01.pdf

Basically it tells me the ABS is integrated into the PCM as well as the 4WAL breaking system on the older 4WAL models, (mainly the ones with two front wheel speed sensors and one for the rear located on the tail-end of trans, as opposed to having two for each rear wheel) which is what I have.

So basically, unless you pull the bulb, or cover it up somehow (tape,paint).... you would have to disconnect the power source from the 4WAL system AND the PCM input to get the light to go out.

I will do a little more research on this in the coming days and keep you guys posted on whether I find an easy wire to chop for lights out in the dash...

I also found this, http://www.autolib.diakom.ru/CAR/Che...RAMS/10137.pdf it's a link to a wiring diagram that was pretty much used on all of the 4WAL systems for a long period, so chances are it will match yours.

Good luck and if anyone attempts this before I get a chance, please post your results/solution. Thanks.


***edit***

And a quick answer to my original question in case anyone was wondering... The EBCM is the EHCU on 4WAL systems like mine, with some components for ABS located in the PCM.

 

hmmm...........i've never come across a 4WAL system that only had one sensor for the rear of the truck-which i believe is actuall defined as a different system (but i can't find my '94 + older manual right now.......).........when i did the disconnect on my '92, i only disconnected the one plug right @ the ABS unit under the hood, and the light went out.

no other cutting or splicing. didn't unplug anything anywhere else, or any of the other plugs on the ABS unit.

since i haven't been driving my truck since Saturday (got stuck driving a POS Sunfire for 5 days), i'll take a peak @ my truck tomorrow morning, see if i can remember which plug it was, see if it'll do the trick on this 2nd gen of mine.

i'll let you know.