Code result
P0E21
Hybrid/EV Battery Pack Coolant Control Valve B Control Circuit Driver Current/Temperature Too High
High severity
What it means
The output driver for hybrid/ev battery pack coolant control valve b reports current or junction temperature above its protection threshold.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Actuator stalled - high stall current
highOne of the most commonly reported causes for this code — check this first.
Control wire shorted to ground
mediumA plausible cause — test and verify before replacing parts.
Pack cell imbalance approaching service threshold
lowLess common, but worth ruling out after the more likely causes.
Related help
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