P2D43 code meaning
A/C Compressor Motor Voltage B High
Powertrain system Generic code P2Dxx codes Check engine light
What P2D43 means
With P2D43 the controller reports that compressor motor voltage B has climbed above the level its power stage can withstand; the compressor controller normally stops the motor to protect its transistors. No manufacturer documents P2D43 on an official public source. GM's hybrid tables show how the voltage A side is treated: the 2011 Volt logs a single sample of 480 V or more as P1ECA, while the 2016 tables classify a reading above 527.25 V as out of range under P0D6A, each Type B. Real overvoltage is rare because the battery holds the bus steady; spikes during charging or regeneration, a faulty converter or charger, or a wrong measurement inside the compressor are more likely. The A/C cuts out; repeated cases call for a check of the high-voltage system.
P2D43 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2D43
- A/C switches off, sometimes only for a while
- Hybrid or EV system warning
Common causes of P2D43
- Most likelyFaulty voltage measurement in the compressor control module
- PossibleVoltage spikes on the high-voltage bus during charging or regeneration
- Less likelyFaulty DC/DC converter or on-board charger
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Ac compressor motorAc compressor moduleWiring harness
What each part of P2D43 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 43 | The exact fault in that area. |
What to do next
- Note P2D43 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2D43
What does P2D43 mean?
P2D43 means "A/C Compressor Motor Voltage B High". With P2D43 the controller reports that compressor motor voltage B has climbed above the level its power stage can withstand; the compressor controller normally stops the motor to protect its transistors. It is a generic code, so it means the same on every make.
Is it safe to drive with P2D43?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2D43 fail an emissions test?
P2D43 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P2D43 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P2D43 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.