Powertrain, generic

P0EB3 A/C Compressor Motor Phase U Current Sensor Circuit Low

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0EB3 means the phase U current signal has fallen below its permitted range. Depending on the sensor design this looks like a large negative current or like no signal at all; either way the controller can no longer trust the U-phase value it needs to drive the motor smoothly. No maker documents P0EB3 publicly. In GM's 2011 Volt, a phase U reading of minus 68 A or lower with the compressor at rest set the older code P0D7B, Type B with MIL after two trips, and a 12 V reset was needed before the test could pass again. Likely causes are a ground short in the sensing path, lost sensor supply or an internal inverter fault. Cooling stays off until the fault clears. Counterpart: P0EB2; the same fault on V and W: P0EB6, P0EB9.

Likely causes

Phase U sensing path shorted to ground
Supply to the phase U sensor missing
Internal fault in the compressor inverter

Symptoms

  • Air conditioning inoperative
  • Fault message after switching the A/C on

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–2,500
Time1–5 h

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

Parts involved

ac compressor motor phase u current sensorac compressor module

Related codes

P0EB2P0EB1P0EB4P0EB6P0EB9P0D7B

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