Powertrain, generic

P0E4F Motor Electronics Coolant Pump A Control Circuit Intermittent/Erratic

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P0E4F covers coolant pump A of the motor electronics loop, which cools the inverter and drive motor, and sets when the signal exchanged with the pump becomes unstable rather than permanently open or shorted. Ford uses exactly this code in the OBD summaries for its hybrid and plug-in hybrid models of 2015 to 2019: the pump reports back to the module, and P0E4F is stored when that feedback is outside the expected frequency or duty cycle for more than 1 s. The check runs continuously from 500 ms after power-up with 6 to 19 V on the 12 V network, next to P0A05 (no response for over 9.25 s), P0A06 and P0A07 (driver faults) and P0C73 (pump reports an internal fault). Loose pins or moisture in the pump connector are typical; overheat protection may cut power.

Likely causes

Loose, corroded or wet pins in the pump A connector

Chafed command or feedback wire that loses contact intermittently

Failing electronics inside the pump sending an unstable feedback signal

Unstable 12 V supply or poor ground at the pump

Symptoms

MIL or hybrid system warning
Power reduction when inverter or motor temperature rises
Fault may clear itself and return later

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€80–700

Time0.5–3 h

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

Parts involved

motor electronics coolant pump awiring harnesshybrid control module

Related codes

P0A05 P0A06 P0A07 P0C73 P0E50

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