Powertrain, generic

P0EAB A/C Compressor Motor Voltage Sensor B Circuit Low

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0EAB is set when the B voltage channel of the electric A/C compressor reports far less than the high-voltage battery actually supplies while the contactors are closed. Typical reasons are a sense line shorted to ground, a broken internal connection or a sensing stage without supply; a supply interrupted upstream, for instance by a high-voltage fuse, produces the same picture and should be ruled out first. No manufacturer documents P0EAB publicly. For the A channel (P0D6B), GM's 2011 Volt uses 190 V or less in 30 of 60 samples, contactors closed and no faults present, Type B. CARB calls for range checks of such inputs where hybrid cooling depends on them. The air conditioning, and possibly battery cooling, fails; the high counterpart is P0EAA.

Likely causes

Voltage sense line shorted to ground
High-voltage supply to the compressor interrupted (fuse, connector)
Measuring stage in the compressor module without supply

Symptoms

  • No cooling from the air conditioning
  • Charging power may be reduced if the battery cannot be cooled

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–2,500
Time1–5 h

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

Parts involved

ac compressor motor voltage sensor bac compressor modulewiring harness

Related codes

P0EAAP0EA9P0EA8P0D6BP2D42

References: gsi.ext.gm.com, law.cornell.edu.