Powertrain
Definition only
Lights the check engine lamp
P2A42: Alternative Fuel Tank B Pressure Sensor Range/Performance
Standardized SAE J2012 code · P2Axx codes
What does P2A42 mean?
The pressure signal of alternative fuel tank B does not match plausibility checks against tank temperature and fill level. Sensor drift.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Sensor zero drifted
- Medium Sensor mounting loose - bias offset
- Low Sensor element aged beyond calibration window
Likelihood is a general estimate across vehicles; your make and model may differ.
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P2A42 in the community
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