Powertrain, generic · Hybrid propulsion

P0A68 Drive Motor B Phase U Current High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0A68 means the current measured in phase U of drive motor B rises above its plausible maximum, either because a real overcurrent flows, for example through damaged insulation, a winding short or a shorted power switch, or because the phase sensor reads too high. No manufacturer documents P0A68 publicly. For the motor A counterpart P0A5F, Hyundai links phase-high codes on the 2017 Ioniq Hybrid to coolant leaking inside the traction motor, together with an insulation fault. A Toyota patent explains why the inverter must react quickly: overcurrent loads the power switches and can destroy them, so the drive is cut. CARB requires monitoring of electric drive components. P0A67 is the low side, P0A6B and P0A6E cover V and W. Motor B is shut down.

Likely causes

Winding short or insulation breakdown in phase U of motor B (e.g. coolant ingress)
Shorted power switch in the phase U leg of the inverter
Phase U current sensor reading too high (gain or offset fault)

Symptoms

  • Hybrid warning and MIL, often with an insulation fault code
  • Sudden loss of drive from motor B

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€400–7,000
Time2–10 h

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

Parts involved

drive motor b phase uinverter

Related codes

P0A66P0A67P0A6BP0A6EP0A5FP0A79

References: patents.google.com, static.nhtsa.gov, law.cornell.edu.