P2B66
Coolant Pump D Control Circuit/Open
Coolant pump D reports a control circuit/open condition. Coolant circulation through the affected loop cannot be commanded reliably.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Open in control wireCommon
- Open pump motorPossible
- Pin pushed back out of connector bodyLess likely
Parts involved
- Coolant Pump D
- Wiring Harness
- ECM
P2B66 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.