P0135 on a Volvo: Causes, Fixes & Repair Cost
🟠 Moderate severity · drivable
Safe to drive, but the sensor warms up slowly and fuel economy and emissions may suffer until the heater circuit is fixed.
What P0135 means on a Volvo
On a Volvo, P0135 means the heater inside the bank 1 upstream oxygen sensor isn't working. The sensor sits before the catalytic converter and uses its heater to reach working temperature quickly after a cold start. With a dead heater, the sensor reads slowly and the engine may run rich while warming up.
Is P0135 common on Volvos?
P0135 is common on higher-mileage Volvos like the S60, XC60, and XC90, where upstream oxygen sensors wear out with age. The heater element inside the sensor fails most often. Replacement is routine, though Volvo parts and labor cost more than average.
Commonly reported on: S60, V60, XC60, XC90.
Symptoms
- Check engine light is on
- Slower sensor warm-up after cold start
- Slightly worse fuel economy
- Possible failed emissions test
Common causes
- most common: Failed O2 sensor heater element
- common: Blown heater circuit fuse or relay
- common: Damaged or corroded wiring or connector at the sensor
- less common: Defective aftermarket sensor
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Replace the upstream oxygen sensor | Yes | $110–260 |
| Replace the blown fuse or relay | Yes | $10–40 |
| Repair the wiring or connector | Mechanic | $100–250 |
Frequently asked questions
Other common Volvo codes
P0135 on other brands
Looking for the full (non-brand-specific) guide? See the P0135 code page →
Browse all Volvo codes: Volvo hub →
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.