Powertrain
generic / SAE
P0E79
Coolant Bypass Valve B Control Circuit High
The coolant bypass valve B reports a control circuit high condition. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberE / 79
Possible causes
- Wire shorted to B+ high
- Coil open medium
- Connector pins corroded - high contact resistance low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 200–1200 €
- Estimated time: 1–5 h
- Component: coolant bypass valve b
- Component: wiring harness
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012