C70 First volvo, ABS/Tracs problems

[aaronturbo]

HI all,

So first off I acquired for basically free a 2002 c70 convert (with a working roof) 107,000 miles and a full dealer history, so so car has a few minor issues im working through.

So had a little scan P1550, however looking through the previous about the ABS/Tracs module problem ( that im very able to solder) i still have a working speedo.... would this still lean on the module or possibly abs rings and or sensor,, im based in kent and really dont want to pay for a dealer scan!


Thanks in advance
Aaron.

[SteveSarre]

hi aaronturbo,

I don't what is causing the code in your case.

But if it was me I would:
Photograph the ABS module from below to get a part number from it. If you can get a cheap one from a scrappie that might be worth getting.
Get a Torq E5 socket so you can undo the ABS module if you need to. (Don't try to make do with the incorrect socket because you can easily strip the bolt heads).
Look at the cogged ring on each hub rings (reluctor rings) and see if they are heavily rusted or chipped.

.. and of course see if anyone has a better suggestion.

HTH
Steve

[Luxobarge]

I assume that as you have a fault code, the ABS light is on and therefore not currently operating?

If the front left sensor were faulty, I'd expect speedo problems, so while it's still possible it's not a high favourite for me.

If the ABS rings were cracked or corroded, I wouldn't expect an ABS light on or a fault code, but would expect it to fire the ABS when braking from time to time - the reason is that dodgy rings cause intermittent pulses from the wheel, so the ABS ECU simply thinks that this wheel is skidding, and does what it's supposed to do, it engages the ABS system.

So the other thing you mention is the ABS module itself - I'd think that this would be favourite, personally I'd get in there and do all the soldering that you are clearly aware of, and see what happens. Bear in mind that the large ABS plug can sometimes give bad connections (mine does it from time to time) so simply re-seating this a few times is a really quick and easy thing to do before pulling the module apart.

[Spawned66]

Originally Posted by Luxobarge

If the ABS rings were cracked or corroded, I wouldn't expect an ABS light on or a fault code, but would expect it to fire the ABS when braking from time to time - the reason is that dodgy rings cause intermittent pulses from the wheel, so the ABS ECU simply thinks that this wheel is skidding, and does what it's supposed to do, it engages the ABS system.

Not on my 99 ME7 C70. I got the ABS light, then the tracs light, then the engine light. Speedo worked fine. Read the code, cleared it, ran ok for a day then happened again.
Anyways, thought it was going to be the ABS module, even bought the torx kit for it just in case. Jacked up the front, turned the wheels to see ABS rings and behold, near side was split, still intact but had a bit of a gap.
I bought new ABS rings but noticed the CV joint while it was still good, it was rusty as hell, guess 21 years it would be.
So, just bought 2 new CV joints that come with ABS rings. Nice Saturday job, fixed ABS issue.

[aaronturbo]

first of all thanks for your suggestions, perhaps I should have gone into more detail,

So i cleared the codes stored, just the p1550, Abs light still on, no Tracs, drive up the road Tracs light comes on, and its the same every start, just abs light, move of then Tracs comes on.

Today I will be jacking the car up to inspect all wheel rings check connections on the sensors and I will also check and re-seat the big connector on the abs module its self... I have ordered a decent soldering iron so should be here in the next few days,,, I was just not sure as all other posts regarding the module failed seem to have no speedo also.

Again thanks guys for your help.
Aaron.

[aaronturbo]

just for those who are having similar issues,

This turned out to be a broken reluctor ring, that had worn the end of the abs sensor away.

couldn't see it until i done the bottom arms and got a closer look, spun the hub with wheel off, the crack was so thin you wouldn't see it with out a torch, and assume that it had expanded at speed and caught the end of the sensor,

Yay no more abs/tracs lights.