P0D71A/C Compressor Control Module Internal Temperature Sensor A Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0D71 is a plausibility test for the compressor control module's internal (CPU) temperature sensor: after a long rest, every temperature in the compressor should be close to its surroundings. GM's 2011 Volt compares it with intake air and with the output-stage sensor and fails above 6 °C in 35 of 40 samples at 250 ms. The 2016 Volt uses more than 22 °C against outside air and the IGBT sensor once the compressor has been off for over 7,200 s, the 2016 ELR 10 °C, and the 2019 Volt 22 °C in 8 of 10 s; outside air has to be above −7 °C. All are Type B with MIL after two trips. A drifting sensor, a faulty reference sensor or a compressor still warm from use can trigger it; range faults are P0D72 and P0D73.
- What you may notice
- Check engine light after two trips
- Usually no noticeable change in A/C operation
- Likely causes
- LikelyDrifting internal temperature sensor in the compressor electronics
- PossibleOutside air, intake air or IGBT sensor used for comparison is wrong
- RareCompressor not fully cooled down when the test ran
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €50 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.