P0E21
Hybrid/EV Battery Pack Coolant Control Valve B Control Circuit Driver Current/Temperature Too High
Generic OBD-II
Common symptoms
What you'll notice
- Check and replace the Hybrid/EV Battery Pack Coolant Control Valve.
- Inspect and repair any loose or damaged wiring connections related to the B Control Circuit.
- Test and replace the Driver Current/Temperature sensor if it is faulty.
- Check and repair any overheating issues with the Hybrid/EV Battery Pack.
- Inspect and repair any potential issues with the Control Circuit Driver module.
Common causes
Most likely first
- Faulty hybrid/EV battery pack coolant control valve
- Malfunctioning control circuit driver
- High current in the hybrid/EV battery pack coolant control valve
- Overheating of the hybrid/EV battery pack coolant control valve
- Electrical issues in the hybrid/EV battery pack coolant control valve
How to diagnose & fix
Work through it in order
- Battery overheating
- Decreased efficiency
- Reduced power and acceleration
- Illuminated warning light
- Malfunctioning hybrid or electric vehicle system
Read & clear P0E21 yourself
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