P2E42 code meaning
Hybrid/EV Electronics Coolant Pump B Performance
Powertrain system Generic code P2Exx codes Check engine light
What P2E42 means
P2E42 is the functional verdict on electronics coolant pump B: the circuits test fine, yet the controller concludes the pump is not doing its job. Two ways of reaching that verdict are documented for pump A. For the 2016 Cadillac ELR, GM checks the result, setting P0CEA when power electronics coolant and charger temperatures drift too far apart after the pump has been enabled for more than 300 s. GM's 2018 tables check the pump itself by filtering the gap between commanded and reported speed (P19FC, Type B). No maker documents P2E42. Stellantis cleared a related performance code of a motor electronics pump B, P0C74, on 2023 Renegade and Compass 1.3 PHEV models by reprogramming. Air, debris, a weak pump or software are candidates; CARB asks for a cooling check where feasible.
P2E42 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P2E42
- MIL and hybrid system warning
- Higher inverter or charger temperatures than usual
- Power reduction or slower charging in hot conditions
Common causes of P2E42
- Most likelyAir pocket after service or slow coolant loss
- PossibleWorn pump B delivering too little flow
- PossibleDebris, kinked hose or clogged cold plate in the loop
- Less likelyControl software needing an update
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hybrid electronics coolant pump bPower electronics coolant loop
What each part of P2E42 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 42 | The exact fault in that area. |
What to do next
- Note P2E42 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2E42
What does P2E42 mean?
P2E42 means "Hybrid/EV Electronics Coolant Pump B Performance". P2E42 is the functional verdict on electronics coolant pump B: the circuits test fine, yet the controller concludes the pump is not doing its job. It is a generic code, so it means the same on every make.
Is it safe to drive with P2E42?
Drive gently and only to a workshop. With P2E42 the car can go into limp mode (reduced power) to protect itself.
Will P2E42 fail an emissions test?
Yes, it can. P2E42 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2E42 to fix?
Difficulty: hard. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P2E42 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.