Powertrain, generic · Hybrid propulsion

P0A39 Generator Temperature Sensor Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0A39 is the high-side counterpart of P0A38: the generator temperature signal stays above the range a working sensor can deliver. Mitsubishi sets it on the 2023 Outlander PHEV when the generator W-phase coil sensor voltage reaches 4.93 V or more for at least 0.5 s. A voltage that close to the reference typically means the sensor circuit is open, a connector is unplugged or a terminal has lost contact, less often a short to a supply. Mitsubishi points to the power drive unit, the coil sensor in the generator and the harness. P0A37 handles implausible but in-range readings, P0A3B a real overheat. No other manufacturer documents P0A39 publicly. The system cannot protect the generator and limits its use.

Likely causes

Open sensor circuit or unplugged generator connector
Spread or corroded terminals at the generator or power drive unit
Generator coil sensor open internally
Signal wire shorted to a supply voltage

Symptoms

  • Hybrid warning or check engine light
  • Generator temperature shows a very low fixed value
  • Generator output or series mode restricted

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–3,500
Time1–6 h

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

Parts involved

generator temp sensorwiring harnesshybrid control module

Related codes

P0A36P0A37P0A38P0A3BP0A33

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