OBD-II code · Powertrain (generic, extended)
P2D42 A/C Compressor Motor Voltage B Low
The voltage B feedback of the electric A/C compressor motor is below the expected window. Phase wire shorted to ground or driver fault.
Is it safe to drive with P2D42?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyPhase B wire shorted to ground
- PossibleOutput driver low-side fault
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–7 h
- Emissions test
- Usually unaffected
- Parts involved
- AC Compressor Motor, Wiring Harness, Ecm
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.