P2ACCReductant Temperature Sensor B Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2ACC is the general circuit code for a second reductant (DEF) temperature sensor outside the tank; the tank sensors have their own series (P205A ff. and P2ADA ff.). Sensor A, coded P2042 ff., is placed by Deutz in the SCR supply path (SPN 4337) and by Volvo and Mack in the DEF pump. Where a B sensor sits is left to the maker, and no manufacturer publicly documents P2ACC. The code captures circuit faults that do not fall clearly under the low or high codes P2ACE and P2ACF. CARB requires circuit monitoring for every input that feeds an emission control. Because DEF heating and the release of dosing depend on this temperature, an SCR warning and, if the fault stays, the usual inducement steps may follow.
- What you may notice
- Check engine light and DEF/SCR warning
- Countdown or speed limitation if the fault persists
- Likely causes
- LikelyConnector of sensor B corroded by DEF residue
- PossibleDamaged wiring between sensor B and the controller
- PossibleDefective reductant temperature sensor B
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.