Although I am not a Volvo owner, for many years I have looked after Volvos for a friend. First, a '94 850 and now a '98 S70 with 90k miles.

The car was recently repaired at a trusted shop to address the dash panel ABS and TRACS lights being on. They found fault codes: 3-1-4 (wheel sensor), 3-2-4 (wheel sensor), and 4-4-3 (pump motor). As a result, they changed the speed sensor assembly. They said that we needed to wait to see if the pump motor codes came back on. If so, they said that it might need a pump motor or ECM replaced. Of course, the lights did come back on.

I am not a mechanic, but have tackled moderate DIY items, like replacing modules. Since my friend is on a limited budget, I was wondering how easy or hard it would be to replace the ABS ECM. I don't think that I could do the pump motor. But I have read that the ABS ECM's are problematic, so I thought it might be a good place to start.

Any advice on what to do would be appreciated. And, if this is something I should leave to the shop, I guess I will do that. They quoted $800 to replace the ECM and I'd like to do better than that if at all possible.

Regards,

John

Amendment: After looking up the ECM part and seeing it had the hydraulic lines attached to it, I think that it looks to be more than I'd want to tackle as a DIY. I would still be interested in any insight anyone might have about the ABS system. I didn't see a pump indicated on Groton's ABS parts list, but I assume the ABS system has one.

 

Since the fault codes did not come back your friend very well may have the broken solder joint syndrome in the ABS module.

Ck this thread:
http://www.matthewsvolvosite.com/for...?p=46827#46827

If you're not into DIY, there are lots of folks who will fix the module if you send it to them. R+R is pretty simple.

Google "volvo abs module repair" and you'll see lots of them..

 

Try here, this gentleman has it down to a science and his prices are very fair. with guarantees.
98 VOLVO S70 CHASSIS ECM ABS MTD ON PUMP AWD | eBay

 

Thank you. I think that the info on the thread and a used module from the ebay seller mentioned by colt1911 will make this a reasonable project for me to undertake.

 

Thank you for the information. I have reviewed the DIY module repair and think getting a used one from this source is the better option for me.

 

Paying $75 for a used one that may have the same issue?

$105 to get it rebuilt here; i haven't used him but heard he's reputable:
Volvo ABS Control Unit Computer General Information

Good instructions on his site too on how to R+R as well.

 

Yes. I agree about getting the re-built one. Very helpful website. Thanks.

 

Had same codes, a coomon problem with Volvo. 99% sure it's not wheel sensors but ABS Module which over time, solder connections break internally. Pain to fix yourself. Midwest Module repair sends you remanufactured module and torx tool/instructions to replace. You send your module back to him with tool. He repairs it for next guy with same prob. You might get mine he repaired.

 

Thank you. I will take a look at Midwest Module. Hope to do this work as soon as the weather cools down a bit.

Interesting that you mention that it was probably not the wheel sensors, which we have already paid to have replaced. Makes me wonder if the shop is just milking this for all they can get. I suppose they could argue that they tried the cheapest repair first.