Powertrain, generic · Hybrid propulsion

P0CEB Hybrid/EV Electronics Coolant Pump A Control Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

The control line of the electronics coolant pump sits at too low a level, typically because it is shorted to ground or the driver cannot pull it up. No manufacturer publishes setting criteria for this code. GM's 2019 HPC2 table names P0CEB only as a blocking code alongside P0CE9, P0CEC and P0CED: while any of them is active, the plausibility test of the electronics coolant temperature sensor (P0CEF) does not run. GM folds a grounded line into P0CE9 in other years, so how P0CEB is used depends on the controller. CARB requires inverter cooling components to be checked for circuit faults. The counterpart for a line stuck high is P0CEC. A shorted line can keep the pump from running, which lets the inverter and charger loop overheat and leads to power limits.

Likely causes

Control wire chafed through and touching body ground
Pump control input shorted internally
Water or corrosion in the pump connector bridging pins to ground
Faulty output stage in the controlling module

Symptoms

  • Malfunction indicator lamp or hybrid warning
  • Electronics coolant pump does not run
  • Power or charging limited as electronics temperatures rise

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–650
Time0.5–3 h

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

Parts involved

hybrid electronics coolant pump awiring harnesshybrid control module

Related codes

P0CE9P0CECP0CEDP2E43

References: gsi.ext.gm.com, law.cornell.edu.