OBD-II code · Powertrain (generic, extended)
P2E78 Hybrid/EV Battery Pack Coolant Temperature Sensor D Circuit Intermittent/Erratic
The ECM detects a circuit intermittent/erratic fault on the hybrid/ev battery pack coolant temperature sensor d circuit. Reading cannot be used reliably for control.
Is it safe to drive with P2E78?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySensor connector not seated
- PossibleNoisy ground reference
- Less likelyConnector with intermittent contact under vibration
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Hybrid Battery Coolant Temp Sensor D, Wiring Harness, Bms
Related codes
- P2D56Hybrid/EV Battery Pack Coolant Temperature Sensor C Circuit Intermittent/Erratic
- P2E75Hybrid/EV Battery Pack Coolant Temperature Sensor D Circuit Range/Performance
- P2E76Hybrid/EV Battery Pack Coolant Temperature Sensor D Circuit Low
- P2E77Hybrid/EV Battery Pack Coolant Temperature Sensor D Circuit High
- P2E79Hybrid/EV Electronics Coolant Pump C Performance
- P2E7AHybrid/EV Electronics Coolant Pump C Overspeed
- P2E7BDrive Motor A Excitation Current Sensor Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.