Powertrain, generic · Hybrid propulsion

P0C4B Hybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C4B refers to the power feed of battery coolant pump A rather than its command line: the controller sees no or only an implausible supply voltage at the pump, typically because a fuse, relay, connector or wire in the feed is open. Ford documents the code on its 2020 hybrids. On the Escape HEV built up to 10 June 2020, bulletin 20-2221 lists P0C4B with other battery codes in the battery energy control module and cures the MIL by reprogramming PCM and BECM; bulletins 20-2293 and 20-2345 name it for the Explorer and Aviator hybrids. Without a software cause, the fuse and relay in the pump feed come first. CARB requires the electrical components of battery thermal management to be monitored. P0C4C and P0C4D are the low and high variants of the same supply.

Likely causes

Battery control module software (Ford Escape HEV, Explorer and Aviator 2020)
Blown fuse or failed relay in the pump supply
Open feed wire or pushed-out pin at the pump connector

Symptoms

  • MIL on
  • Battery coolant pump not running, power limited when warm

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€20–700
Time0.3–2.5 h

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

Parts involved

hv battery pack coolant pump awiring harnessbms

Related codes

P0C4CP0C4DP0C47P0C48P0C49P0CFF

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