Powertrain, generic · Hybrid propulsion

P0D71 A/C Compressor Control Module Internal Temperature Sensor A Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modeNo

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.

Likely causes

Drifting internal temperature sensor in the compressor electronics
Outside air, intake air or IGBT sensor used for comparison is wrong
Compressor not fully cooled down when the test ran

Symptoms

  • Check engine light after two trips
  • Usually no noticeable change in A/C operation

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€50–2,500
Time0.5–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

ac compressor cm internal temp sensor aac compressor module

Related codes

P0D70P0D72P0D73P0D76P0072P0073

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.