Powertrain
Definition only
Lights the check engine lamp
P26AC: Engine Coolant Bypass Valve B Control Circuit / Open
Standardized SAE J2012 code · P26xx — Computer and output circuits
What does P26AC mean?
The controller cannot drive the second coolant bypass valve. The associated cooling sub-loop cannot be regulated.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Open coil in bypass valve solenoid
- Medium Broken control wire
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P26AC on the same make and model first.
P26AC in the community
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