Powertrain, generic

P0EF5 Drive Motor C Temperature Sensor Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0EF5 covers a drive motor C temperature signal that jumps or drops out for short moments instead of staying wrong. Because of the thermal mass of a traction motor, the winding temperature can only change slowly; a step of many degrees within milliseconds therefore points to the wiring and not to the motor. Loose or corroded pins at the motor connector, leads chafing near moving parts or a cracked sensor lead are typical. No manufacturer documents P0EF5 publicly, and its drive motor A and B siblings P0A2E and P0A34 are not listed in the published Ford and GM tables either; Ford only runs open and short checks on its coil sensors with a 200 ms monitoring window. CARB requires hybrid systems to watch electric motor performance. Warnings that appear and vanish, sometimes with brief power cuts, are typical.

Likely causes

Loose or corroded pins in the motor connector
Harness chafing at brackets or moving parts
Cracked sensor lead inside the motor that opens with vibration or heat

Symptoms

  • Warning lamp that comes and goes
  • Short power interruptions of motor C, often on rough roads
  • Jumping motor temperature in the live data

Repair estimate

DifficultyHardWorkshop job
Parts and labour€50–2,000
Time0.5–6 h

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

Parts involved

drive motor c temp sensorwiring harnesshybrid control module

Related codes

P0EF1P0EF3P0EF4P0A34P0A2E

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