OBD-II code · Powertrain (generic, extended)
P2BAF NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 1
The heater sense feedback of NOx sensor 1 on bank 1 reports values that do not match expected operation. The sensor warm-up cycle does not behave as the diagnostic expects.
Is it safe to drive with P2BAF?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyNOx sensor aging
- PossibleHigh resistance in heater circuit
- Less likelySensor element aged beyond calibration window
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–4 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Nox Sensor, Nox Heater Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.