OBD-II code · Powertrain (generic, extended)
P2A42 Alternative Fuel Tank B Pressure Sensor Range/Performance
The pressure signal of alternative fuel tank B does not match plausibility checks against tank temperature and fill level. Sensor drift.
Is it safe to drive with P2A42?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySensor zero drifted
- PossibleSensor mounting loose - bias offset
- Less likelySensor element aged beyond calibration window
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–4 h
- Emissions test
- Likely to fail
- Parts involved
- Alt Fuel Tank B Pressure Sensor, Wiring Harness, Afcm
Related codes
- P2A47Alternative Fuel Tank C Pressure Sensor Range/Performance
- P2A3FExcessive Time to Enter Alternative Fuel Control
- P2A40Alternative Fuel System - Injector Leakage to Rail Detected
- P2A41Alternative Fuel Tank B Pressure Sensor Circuit
- P2A43Alternative Fuel Tank B Pressure Sensor Circuit Low
- P2A44Alternative Fuel Tank B Pressure Sensor Circuit High
- P2A45Alternative Fuel Tank B Pressure Sensor Circuit Intermittent/Erratic
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.