Powertrain
Definition only
Lights the check engine lamp
P2B85: Engine Coolant Pump Underspeed
Standardized SAE J2012 code · P2Bxx codes
What does P2B85 mean?
The engine coolant pump runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or supply voltage low.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Mechanical load increased (binding)
- Medium Supply voltage low under load
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2B85 on the same make and model first.
P2B85 in the community
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