OBD-II code · Powertrain (generic, extended)
P2B21 Hybrid/EV Electronics Coolant Temperature Sensor B Range/Performance
The vehicle hybrid control module detects a range/performance fault on the coolant temperature sensor B that monitors the power electronics cooling loop.
Is it safe to drive with P2B21?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySensor characteristic drifted
- PossibleSensor mounting displaced
- Less likelySensor element aged beyond calibration window
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 Electronics Coolant Temp Sensor B, Wiring Harness, Hybrid Control Module
Related codes
- P2B25Hybrid/EV Electronics Coolant Temperature Sensor C Range/Performance
- P2B1ECylinder 8 Injection Pulse Offset Not Learned
- P2B1FCylinder 8 Injection Pulse Offset Exceeded Learning Limit
- P2B20Hybrid/EV Electronics Coolant Temperature Sensor B Circuit
- P2B22Hybrid/EV Electronics Coolant Temperature Sensor B Circuit Low
- P2B23Hybrid/EV Electronics Coolant Temperature Sensor B Circuit High
- P2B24Hybrid/EV Electronics Coolant Temperature Sensor C Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.