Powertrain, generic

P0EF1 Drive Motor C Temperature Sensor Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0EF1 is the general circuit code for the temperature sensor of drive motor C, the third traction motor on vehicles with three or more electric machines. It must not be confused with P2DB1, which means sensor C inside drive motor A. Volvo Trucks lists P0EF1 with failure type 09, component failure, for its electric trucks in remote diagnostic bulletin RD21-022; it names connector, wiring harness, the motor temperature sensor itself and an unsupported configuration as possible causes and sends the technician to Tech Tool for the detailed steps. The general code is used when the fault is not classified as low or high, which have their own codes P0EF3 and P0EF4. Without a usable winding temperature the controller has to protect motor C and limits its output.

Likely causes

Loose, corroded or damaged connector of the motor C temperature sensor
Chafed or broken sensor wiring
Temperature sensor in the winding failed
Controller configuration not matching the installed motor (Volvo RD21-022)

Symptoms

  • Reduced drive power
  • Warning lamp for the electric drive
  • Motor temperature shown as invalid in the scan tool

Repair estimate

DifficultyHardWorkshop job
Parts and labour€50–2,500
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

P0EF2P0EF3P0EF4P0EF5P0A30P2DB1

References: static.nhtsa.gov, fordservicecontent.com, law.cornell.edu.