I have a 89 convertible, the antilock light warning light wont turn off. After running many tests the dealer says it might be a bad EBCM. He said it would be about $1000 just for the new unit. Does anybody know of any aftermarket replacements? Dealer still running more tests before he tries replacement.

 

Welcome

Does the Dealer have all the required test tools? Most don't!

IMHO, the ecm has nothing to do with the ABS sysytem. There is an ABS Controller and modulator as part of the system, everything is located in the storage compartment behind the drivers seat. I don't have my Helms manual handy for suggestions.

Dealer really needs some special test euipment

:seeya

:steering:

 

Seems like it could be something as simple as a vehicle speed sensor. ABS uses these to see if any slip occurs. If it is in fact seperate from the ECM, it wouldn't throw a code.

 

Have them vefiry without a doubt what the bad part is since your Vette is already there. Then call The Last Detail Corvette parts at 1888 LAST DETAIL to purchase the part for a lot less than what the dealer will want for it. Then install it yourself if you can. If they can find one, they will beat the dealer's price by a long shot.

I just had the same problem with my 86. My ABS light had always been on the whole time. Busted out my 86 Shop Manual and did a few simple checks. The wiring was good. Found that the ABS Control Module Relay located under the storage compartment behind the driver's seat was done. It was completely corroded, and sounded like something was loose inside. I opened it up, and all the electronics were nothing but a pile of rust and severe corrosion. It fell apart in my hands. I ordered one today from The Last Detail and they gave it to me for half price of what the dealer wanted.

For the future, I would suggest the purchase of a Shop Manual for your 89. There are tons of preliminary and function checks to do yourself for just about everything on the car, before you take it to a dealer. I have saved lots of money in just the few month that I have had my Shop Manual. It's a must have. You can get one on ebay or here on the forum.




[Modified by 86PACER, 12:48 AM 4/16/2004]

 

The ABS system consists of the following (besides the normal brake components)
Control Module
Contol Module Relay
Modulator Valve
4 Wheel speed sensors
Toothed Ring at each wheel
Lateral Acceleration Switch
ABS warning light

Most of which is all located under the storage area behind the driver's seat as previously posted.

Which one of these items do you mean by "EBCM" that is supposed to cost $1000.00 for it alone?




[Modified by 86PACER, 12:49 AM 4/16/2004]

 

Thanks for all the info. I just got off the phone with the dealer, he said they have it narrowed down to the valve relay, the pump relay, the speed sensor, or the ebcm. If I take the time to try and fix it myself, would it be a problem to drive it in the mean time?

 

My 87 service manual says the module on verts is located under the left rear speaker. Also two things from Richard Newton's book: 101 Projects for Your Corvette 1984 - 1996" "I want to take a second to remind you that an ABS failure is not a brake system failure." and pertaining to the ABS system: "About the only time that something goes wrong is when a wheel sensor fails. That's the most common problem with the ABS system." As the other Forum member stated: Buy a GM shop manual. It can save you hundreds of $ even on one job! :blueangel:

 

Your brakes will still work just fine. Even if the ABS is completely disabled, your brakes will work just fine. You can drive the car all you want, but you will not have ABS, that is all.