Powertrain, generic · Hybrid propulsion

P0A4A Drive Motor B Position Sensor Circuit Overspeed

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0A4A reports that the speed calculated from the motor B resolver exceeds the motor's permitted maximum. Mitsubishi uses it for the rear motor of the 2023 Outlander PHEV: set at 12,500 rpm or more for at least 1 s with supply above 8 V, and only judged once the rear position sensor codes P0A45, P0A46, P0C57, P0C58, P0C61 and P0C62 are ruled out; otherwise the rear motor assembly is replaced, bearing damage being one listed cause. GM uses its own code P1B0E (above 11,500 rpm, Type A) for this check on the second motor of its two-mode trucks. CARB 1968.2 requires monitoring of electric drive components. P0A44 is the motor A twin. Expect the rear motor to be shut off to protect it, with less traction.

Likely causes

Fault in the rear motor assembly, e.g. damaged bearing or control unit (Mitsubishi)
Real overspeed from rear wheel spin on low grip
Disturbed resolver signal producing a false speed value

Symptoms

  • Rear electric drive shut off, front-wheel drive only
  • Hybrid/EV warning and MIL
  • Reduced acceleration in limp mode

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–7,000
Time1–12 h

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

Parts involved

drive motor b position sensordrive motor bhybrid control module

Related codes

P0A45P0A46P0A44P0C57P0C61

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