Powertrain, generic · Hybrid propulsion

P0D73 A/C Compressor Control Module Internal Temperature Sensor A Circuit Low

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modeNo

P0D73 is the low-signal circuit code for the internal (CPU) temperature sensor of the compressor control module. For an NTC sensor a low signal corresponds to an implausibly hot reading. GM sets it above 274 °C in the 2011–2015 Volt and 2016 ELR, and above 150 °C in the 2016–2019 Volt, where the compressor itself detects the condition and reports it over GMLAN; counting is 30 of 60 samples at 50 ms, 40 of 50 at 100 ms or 4 of 5 s depending on the year, Type B. Values like these suggest a shorted sensor rather than real heat, although genuine overheating of the electronics should be ruled out by checking. The compressor may limit or stop operation. The cold-side code is P0D72, plausibility P0D71.

Likely causes

Short circuit in the internal temperature sensor path
Real overheating of the compressor electronics
Faulty value transmission to the host controller

Symptoms

  • Check engine light after two trips
  • Air conditioning reduced or switched off

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–2,500
Time1–5 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

P0D72P0D71P0D70P0D74P0D78

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