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.
The voltage B feedback of the electric A/C compressor motor is below the expected window. Phase wire shorted to ground or driver fault.
Common causes
- high
Phase B wire shorted to ground
One of the most commonly reported causes for this code — check this first.
Typical part cost: $330-2200
- medium
Output driver low-side fault
A plausible cause — test and verify before replacing parts.
Typical part cost: $330-2200
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P2D42 mean?
P2D42 means "A/C Compressor Motor Voltage B Low". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2D42?
phase b wire shorted to ground; output driver low-side fault — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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