97 850 GLT ABS/TRACS Problem

John Kelway wrote: : Can you help with my 1997 850 GLT Estate with only 87K Miles on the clock? : The ABS/TRACS light comes on very occasionally (6 times in the last 2000 : miles) usually in hot temperatures. After the engine has been switched off : for 15 minutes or more the lights are out and everything is ok again for the : next few days. Can anyone please explain what the likely fault may be? : Thanks : John.

Its very likely your ABS controller is dying. Do a google search on 850 abs and you will find plenty of info on this subject.

Most likely it's the ABS computer, it's a common problem. If you can find someone to read the codes, you'll see you have a failure in the right rear sensor. However the problem is with the circuitry inside the ABS computer, not with your sensor.

Another, less common problem is the ignition switch, but this is accompanied by inability to shift out of park without using the shiftlock release button, and a few other things not working as well.

I seem to have a similar problem and am debating whether to let the dealer replace it ($450 + labor) or remove it myself and have Vic Rocha

a "repair and upgrade" ($130). Does anyone know whether eitherof those options would get me newer firmware in the ABS computer? Vic Rocha's site mentions heat buildup. That definitely does not seem to be my problem. In fact, the only time the ABS and TRACS lights have stayed off lately for more than a minute or two was after a seven-hour trip. When I stopped for gas, they went out at 12 MPH and stayed out until I got home. They promptly came on again the next day.

Heat buildup is one possibility, but I've seen this to be random. I had to change the computer in my 98 S70 for this reason. Sometimes the light would be on at startup, sometimes it would come on after a few seconds, or minutes, or not at all. Fortunately for me I also have a 98 V70, a swap of computers moved the problem to the other car. Back when I needed to do this I was not aware of any repair options. (The V70 still has it's original ABS computer, 6 1/2 years and 125 000 km, touch wood!)

If I was you, I'd read the codes, write them down, clear them and then wait for the lights to come on again.

Thanks. I already contacted Victor and he said the pre-96 models didn't have that problem, but that the 94's (mine) have a known ignition switch problem that causes those lights to come on. But it seems strange to me that an ignition switch problem would only occur on hot days.

It is just a matter of time. It seems that these units eventually have a nearly 100% failure rate.

John

The codes for the ABS failure are often wrong. They often point people to a "bad" wheel sensor where there is not a bad sensor. In this case you can end up spending extra time and money going by the book.

John

After all the messages in this thread, I'm not sure what your "these units" refer to...