Powertrain, generic (extended)

P2E45 Hybrid/EV Electronics Coolant Pump B Enable Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Some designs switch electronics coolant pump B on through a separate enable line or a relay, independent of the speed command; P2E45 reports a fault in that path. GM's 2018 hybrid tables show the scheme for pump A: with the enable output active, more than 0.6 A on the line counts as a short to ground (P1F44); with it inactive, more than 35 µA or a line voltage under 4.5 V counts as a short to voltage (P1F45), each after 16 of 20 samples at 250 ms, Type B. The 2016 tables list the same pair. Mitsubishi's 2022 Outlander PHEV powers its electric water pump through a relay energised by the PHEV-ECU and names that relay among the causes of its pump speed code P10D9. No manufacturer documents P2E45 itself. Without enable the pump stays dead although the command signal is fine. Pump A's code is P0CED.

Likely causes

Enable wire open or shorted between module and pump
Pump relay or its fuse failed, where the design uses one
Faulty enable output in the controlling module

Symptoms

  • Pump B never starts although commanded
  • MIL and hybrid or charging warning
  • Power or charging limited as electronics heat up

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–600
Time0.5–2.5 h

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

Parts involved

hybrid electronics coolant pump bpower electronics coolant loop

Related codes

P2E41P2E43P2E44P0CED

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