Powertrain
Definition only
Lights the check engine lamp
P2B66: Coolant Pump D Control Circuit/Open
Standardized SAE J2012 code · P2Bxx codes
What does P2B66 mean?
Coolant pump D reports a control circuit/open condition. Coolant circulation through the affected loop cannot be commanded reliably.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Open in control wire
- Medium Open pump motor
- Low Pin pushed back out of connector body
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2B66 on the same make and model first.
P2B66 in the community
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