I’m posting here to get insight, advice, or honestly just to see if anyone has gone through anything similar. I have a 2010 Volvo XC60 (3.0L Turbo AWD) and it’s been an exhausting and expensive journey—starting with long-term ABS/DSTC issues and now including a P0420 code, electrical problems, and confirmed water damage.
ABS Trouble That Never Really Ends
This has been an issue for several years. The ABS/DSTC light first appeared years ago, then after repeated repairs it finally went away for about a year—until it came back with a vengeance.
Since then, I’ve had the ABS/DSTC worked on by multiple mechanic shops, and none of the repairs have truly fixed the problem. So far, repairs have included:
- Multiple wheel speed sensors replaced
- ABS wiring harness replaced
- ABS control module removed and rebuilt
- Various diagnostics across multiple visits
- City Safety Service
- ECM work
- New tires, battery, wiring, electrical everything, speed sensor covers, rear differentials, spark plugs, and anything else possible
The latest shop had the car for seven months (yes, really), claiming the delay was because they kept receiving faulty ABS replacement parts. When I finally got it back, the ABS/ DSTC light was off—but only briefly.
“Engine System Service Required” Came First
The day after I picked up the car, I got a dash warning: “Engine System Service Required.” Then a few days later, the ABS/DSTC light came back on. It later disappeared again, and the mechanics couldn’t get it to reappear, so they assumed it was tied to the engine system alert and cleared the code.
That engine alert came back again shortly after—and now the ABS/DSTC warning is back too. It’s a cycle that repeats no matter how many times the codes are cleared or parts replaced.
New Issue: P0420 – Catalyst System Efficiency
After they replaced my fuel rail pressure sensor (following a P0190 code), I started getting a P0420. Two different OBD2 tools confirmed it: Catalyst System Efficiency Below Threshold – Bank 1.
- My fuel pressure and voltage are currently normal (~380 kPa, 13.6–13.7 V).
- My catalyst temp is around 675°F, so it’s heating properly.
- BUT—O2 Sensor 2 (post-cat) is fluctuating from 0.05V to 0.75V, which usually indicates the cat is no longer filtering gases efficiently.
So now it looks like the catalytic converter may be degraded, likely due to the long period where the fuel pressure sensor was sending faulty data.
Water Damage (Bonus Round!)
The most recent mechanic also found water leaking in through the rearview mirror area and under the steering wheel, likely due to clogged sunroof drains. On top of all the mechanical issues, the car was returned to me covered in mold, with mildew inside and chipped paint outside. This water damage may be playing into the electrical issues too.
Despite all of this:
- The ABS light is still on
- The “Engine System Service Required” alert keeps coming back
- I now have an active P0420
- Gas mileage has significantly declined
- And I’m still not confident in the shop’s repairs or diagnostics
Questions
- Have you had an ABS issue like this that was ever truly resolved?
- Anyone had experience with repeated faulty ABS parts?
- Could unresolved fuel pressure sensor faults actually damage the catalytic converter like this?
- Has anyone filed an insurance claim for water intrusion and electrical failure?
- Or had their XC60 declared a total loss for similar compounding issues?
I loved this car when it worked (minus immediately replacing the rear differentials when I purchased it) But I’m now juggling repairs, refund attempts, and the possibility of filing a total loss claim or trying to sell it off. I’d appreciate any shared experience or advice!