P23C6
Engine Coolant Bypass Valve C Control Circuit Driver Current or Temperature Too High
The driver stage of the coolant bypass valve C reports excessive current draw or thermal protection trip - typically a sticking valve drawing too much motor current.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Common causes
Ordered by how often each turns out to be the cause.
- Motor overloaded by jammed valveCommon
Parts involved
- Coolant Bypass Valve C
P23C6 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.