96 850 turbo sedan - ABS and TRACS stay lit Topic is solved

[Dave in Maine]

850 turbo sedan, automatic trans, approx 215k mi actual, odo reads 190k.

I think this is something other than the "worn ignition switch" issue. I've had that happen, where jiggling the key both makes the lights go out and restores things like turn signals and speedo and releases the transmission lock. I have not changed the ignition switch. It does this with either key.

This time, when I start the car the ABS, TRACS and "needs service" lights come on (I think elapsed mileage makes it think it needs an oil change). After a little while the "needs service" goes out but the ABS and TRACS stay on, but the turn signals and speedo work, the transmission is not locked up, etc.

I had the ABS module replaced about 15 months ago (<15k mi) with a rebuild from the specialist in Tecumseh. Last time it was slippery (it's winter) the ABS worked fine. So, unless there's something radically and suddenly wrong there I'm inclined to doubt it's a module. I don't fiddle with the TRACS, period.

Ideas? Could this just be another stage of the "worn ignition switch" issue? Something else? My first thought is to take a pencil eraser to the keys and then a blast of contact cleaner into the switch. More ideas?

Thanks in advance to all you experts!

[cxf]

From what I have read sounds like the abs module. I know you replaced it but nothing says the new one can't go south again. Btw, i have the same exact car with the same symptom except mine will go off after sitting for a while(cool down?) . Now that it is warming up and my p.o.s. pickup truck is almost ready I will be replacing my abs module with the refurbed unit from another board member here. Have you spoken to the place you got yours from to get some input on the problem you are having? Perhaps they offer a warrantee, 15 months is not very long.

[erikv11]

I would check the sensors because it is free (viewtopic.php?t=41538) but it does sound like the rare case of Midwest ABS module rebuild gone bad, in any case send email to MattyMoo there and he will likely help you troubleshoot. They have a Lifetime Warranty and are super helpful.

[Matty Moo]

Well, I can't help Dave if he doesn't get ahold of me. I really hate splitting communication on two different platforms as it creates a mess.

Rule of thumb.... If one day the abs lights suddenly come on and stay on to never go off again thats usually something outside of the module.

With the age of the cars external faults are common now. I move 1/3 of what I used to but spend 4x the amount of time on support

[abscate]

The mechanical part of the switch where the key goes has nothing to do with the electrical part on the left.

Pick a private comm channel with vendors and stick to it..

[Dave in Maine]

I got some time at my mechanic's yesterday afternoon. I had scheduled that to do some diagnosis on something else (which turned out fine).
While there, we put it on his industrial-strength code reader which came back with "right rear wheel speed sensor".
So I'm going to go in that direction before fiddling with the module - the issue just didn't "feel" like a bad module to me.
No offense intended to anyone, and thanks to all for the help.

[erikv11]

I got some time at my mechanic's yesterday afternoon. I had scheduled that to do some diagnosis on something else (which turned out fine).
While there, we put it on his industrial-strength code reader which came back with "right rear wheel speed sensor".
So I'm going to go in that direction before fiddling with the module - the issue just didn't "feel" like a bad module to me.
No offense intended to anyone, and thanks to all for the help.

Check out the first line of my post, it is a link with instructions on how to test the sensors. But yours is bad almost certainly, next is to read up on how to extract the sensor from a 20 year old rear axle hub that has lived its life in Maine - ugh.

[Dave in Maine]

Following up - we replaced both rear wheel speed sensors (they are wired into one connector) and while it was a bit of a job it's done and the lights are gone. Except when the ignition key needs wiggling, but that's a different issue.
It was not a bad ABS module.
Thanks to all who helped out here. Let's mark this one "Solved".

[erikv11]

How did you get the sensors out of the hubs?

[abscate]

They attach with one Torx screw and then a light pressure fit into the hub. I did have one of mine get stuck and I had to hammer it out, which ruined it

You can replace them singly by removing the connectors from the pin, too