Powertrain, generic

P0EAA A/C Compressor Motor Voltage Sensor B Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0EAA flags a B voltage reading at the top of, or beyond, the plausible range of the compressor supply. Since the battery cannot really deliver that much, the cause usually lies in the measurement itself: an open or shorted sense path, a failed voltage divider inside the compressor or a wrong reference. No manufacturer documents P0EAA publicly. GM's 2011 Volt judges the A channel this way (P0D6A): 440 V or more in 30 of 60 samples taken every 50 ms, Type B with MIL after two trips; a single sample at 480 V or more triggers a separate maker code. A genuinely high bus voltage would also show up in battery and inverter codes, which helps to tell the two apart. The compressor normally shuts down; the low counterpart is P0EAB.

Likely causes

Failed voltage divider or reference in the compressor module
Sense line shorted to a higher potential
Actual overvoltage on the high-voltage bus

Symptoms

  • Compressor stops, cabin is not cooled
  • Warning in the climate control display

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 motor voltage sensor bac compressor modulewiring harness

Related codes

P0EABP0EA9P0EA8P0D6AP2D43

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