S70 Tracs/ABS problem Topic is solved

shegarty · Post by **shegarty** » 27 Jul 2025, 10:19

Vova585 wrote: 27 Jul 2025, 09:28
If you changed input from RR to LR inside the connector and issue moved to LR- your issue is actual sensor or a wire assembly.

My thoughts exactly - I haven’t bothered to check the length of wire but I was able to remove the sensor and clean it up but reinstalled it is still giving the same error code. The sensor looks original so at this point I’m just going to order a new set and go ahead and replace both of them. Maybe I’ll find something on removal.

RonMac · Post by **RonMac** » 11 Aug 2025, 19:28

• Wheel Sensor Fault:
This fault emerged a few years after I had successfully repaired the ABS module on my 1998 S70. So I replaced one of the front wheel sensors with a new one and also spliced in fresh wiring where flexing may cause more stress. Despite this the same fault code persisted.
• ABS Module:
So, although years previously I had re-soldered the commonly reported, faulty joints inside the ABS module, I decided to revisit the repair. On the second tear-down, I targeted and re-soldered a different set of joints—specifically those associated with the wheel sensor input, as flagged by the fault code. This instantly and permanently fixed the new wheel sensor issue.
If your re-manufactured ABS module was only repaired at the usual suspect joints, I wouldn’t rule it out as the source of the ongoing fault. It may still require further attention—particularly re-soldering of additional dry or defective joints. From what I understand, the original ABS modules manufactured in the Philippines suffered from insufficient heating during soldering, which contributed to latent circuit board issues that manifest years later.
BTW, I have spare, front & rear, new wheel sensors that I no longer need. (they rarely fail).

shegarty · Post by **shegarty** » 12 Aug 2025, 07:12

I ended up replacing both rear wheel speed sensors as they come as a pair in one harness. The rebuilt unit was a XEMODEX unit and they have a pretty good reputation and warranty so I figured it probably wasn’t a fault in their work. Seems to be pretty good so far, it’s been about a week or so now.