Code result
P0B39
Motor Electronics Coolant Pump B Control Circuit Low
High severity
What it means
The motor electronics coolant pump B control circuit reports a control circuit low condition. Power electronics cooling cannot be commanded reliably on branch B.
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
Control wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Internal short in pump motor
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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