Powertrain, generic

P0E50 Motor Electronics Coolant Pump B Control Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0E50 is the intermittent or erratic fault of the control circuit for coolant pump B, the second electric pump some hybrids use in the inverter and motor electronics cooling. No manufacturer documents P0E50 publicly. The closest published example is Ford's pump A version, P0E4F, stored when the pump's feedback leaves its expected frequency or duty cycle for over 1 s. Second pumps of this kind are in service: on the 2024 Jeep Compass 4xe, Stellantis bulletin 08-200-24 cures the pump B performance code P0C74 by reprogramming the hybrid control processors. CARB requires inverter cooling outputs to be monitored for circuit faults. Steady open, low and high faults of pump B are P0B38 to P0B3A. Short dropouts briefly reduce coolant flow and may trigger a power limit.

Likely causes

Intermittent contact at the pump B connector or a harness splice
Pump B electronics producing an unstable signal
Control module software evaluating the pump signal too strictly

Symptoms

  • Warning light that appears now and then
  • Temporary power reduction under high load or heat

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–650
Time0.5–3 h

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

Parts involved

motor electronics coolant pump bwiring harnesshybrid control module

Related codes

P0B38P0B39P0B3AP0C74P0E4F

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