Powertrain, generic · Hybrid propulsion

P0A30 Drive Motor B Temperature Sensor Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0A30 is the general circuit code for the temperature sensor in the second traction motor (motor B). It is meant for faults the control unit can see on the sensor line but cannot classify as too low, too high or implausible. No manufacturer documents P0A30 publicly; GM two-mode hybrids and Mitsubishi (rear motor of the 2023 Outlander PHEV) use the specific codes P0A31 to P0A33 for the same sensor instead. CARB 1968.2 requires hybrid components whose failure can affect emissions to be monitored for circuit faults. Without a valid winding temperature the motor cannot be protected against overheating, so the system usually cuts electric drive power and lights a hybrid warning.

Likely causes

Loose, corroded or damaged connector between motor B and its control module
Chafed or broken sensor wiring at the drive unit
Thermistor in the motor winding failed (often only replaceable with the motor)
Faulty sensor input in the motor control module

Symptoms

  • Hybrid system warning or check engine light
  • Reduced electric drive power
  • Motor B temperature missing or implausible in live data

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–3,000
Time1–6 h

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

Parts involved

drive motor b temp sensorwiring harnesshybrid control module

Related codes

P0A31P0A32P0A33P0A34P0A35P0A2A

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