1996 850 Speedometer stopped working & Tracs Light Off

[five_w_coupe]

For the last few years the Tracs light and ABS light have been on in my '96 850 wagon (300k miles and counting). I removed the ABS Controller to read the serial number with hopes of finding a salvage yard replacement (yes, I tried the quick-fix soldering the suspect joints to no avail). When I reinstalled the controller, the speedometer stopped working, the Tracs light went out but the ABS light is still on. I have read that the speedometer problem maybe related to either the ABS Controller/Cruise Control or the ignition switch. To avoid the "rookie technician syndrome" of replacing one thing at a time until the problem goes away, how do I best trouble shoot the problem. I do not have a Volvo code reader and the car is not throwing any codes anyway.
Help Please.

[Ozark Lee]

Re-seat the large hooded connector. The connector will trick you and you will think it is seated when it isn't. The catches on the back of the hood need to engage the pins on the ABS module for it to draw back into the socket correctly.

...Lee

[esl_97_850_T5]

You needn't limit yourself to only searching for the specific part # that is on your car's ABS module.

Matty Moo seems to say on his site that part #s 9162675, 9140774, and 8602266 are interchangeable for a '96-'97 850 with TRACS.

You might find those 3 part #s on '96-'97 850 with TRACS or '98 S70/V70/V70R/C70/XC70 with TRACS.

[esl_97_850_T5]

+1 on Lee's idea to re-seat the large hooded connector.

It's tricky how you have to partially seat the connector, move the slides down a bit, partially seat the connector a little more, move the slides down a bit more, until the connector is finally fully seated. It normally takes 3-4 iterations to get it fully seated.

Of course, you could have messed up something in the re-soldering. But reseating the connector would be the first thing to check.

[Matty Moo]

On a car with Tracs if you only have the ABS light on without the TRACS light it generally means that there is either no power to the unit of the large harness isn't on correctly.

That large harness doesn't like to seat all the way.

[five_w_coupe]

Thank you all very much for your quick responses. But when I pushed it back down as suggested, that fixed it. As much as I hate to, I have to admit, I broke the "Hood". Now I have to figure out how to fix the latching hood. Any ideas and suggestions would be greatly appreciated. Next time I will ask before I start trying to fix something I am not that familiar with, especially when I am not real sure how to get it apart. Brute force isn't always the best technique, it works, but something else always gets broken To think I thought I was a darn good Engineer, and certainly a decent mechanic (self-taught). I've been twisting wrenches on my own cars for the past 48 years, I still am learning about the "new car stuff". BTW New for me is any car built after 1976 Personally, I prefer the 30's thru 60's
Cheers,
Roger

[Matty Moo]

I'm all about doing things right, but I'll tell you not to waste your time trying to fix it. They break all the time. All you have to do is put those plastic slides back in and engage the slides yourself while pushing down on the harness.

My s70 has just the head of the harness, no slides and no plastic hood.

[five_w_coupe]

Thanks for the "feel-better-about-that" . But now I am curious as to why my '96 850 is starting to run rough when I put it into gear? The roughness feels like the ABS cycling and is somehow pulsing the fuel supply. One other thing I should mention, just in case, when I was in the process of trying to determine the speedometer problem, I replaced the speed sensor. I didn't mess anything up with that connector, so I am in a bit of a quandary as to why the Old Gal is running rough only when I put it into gear? It smooth's out once I get going but it