Powertrain, generic · Hybrid propulsion

P0C7A Drive Motor B Inverter Voltage Too High

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0C7A is the overvoltage code for the inverter of drive motor B, which on many all-wheel-drive hybrids is the rear motor. Mitsubishi documents it for the Outlander PHEV: in the 2018 model the rear motor control unit has a hardware high-voltage switch that closes at 420 V, a higher limit than the 370 V of the front unit, and the code sets after a single trip with the power stage active or after 0.5 s with it switched off. The manual blames the high-voltage circuit or the rear control unit and starts with the rear battery cable connections; the 2023 model keeps the code under a rear-motor overvoltage name. Regeneration spikes, contactor events and sensing errors are the usual suspects. Expect a warning lamp and reduced drive power.

Likely causes

Rear battery cable connection loose at the rear motor control unit
Rear motor control unit or its voltage detection faulty
Voltage spike from regeneration or a contactor event

Symptoms

  • Hybrid or EV warning lamp
  • Reduced drive power, rear axle drive may be unavailable

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–4,000
Time0.5–6 h

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

Parts involved

drive motor b inverterdc link capacitor

Related codes

P0C79P0C7BP0A79P0DA4

References: mitsubishitechinfo.com, mitsubishitechinfo.com, law.cornell.edu.