Powertrain
generic / SAE
P26A6
Engine Coolant Bypass Valve A Position Sensor Circuit Low
The bypass valve A position sensor signal is below the lower diagnostic threshold. 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
GroupP2
Range / number6 / A6
Possible causes
- Internal short in sensor element high
- Signal wire shorted to ground medium
- Connector pins corroded - high contact resistance low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 100–600 €
- Estimated time: 0.8–2.5 h
- Component: bypass position sensor a
- Component: wiring harness
- MIL / check engine light
Sources
References
sae:J2012