P26A9
Engine Coolant Bypass Valve A Position Sensor Stop/Minimum Stop Performance
During self-calibration the bypass valve A position sensor never reached the minimum mechanical stop. The position reference cannot be zeroed.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Sediment prevents valve from reaching minimum stopCommon
- Sensor not aligned with valve shaftPossible
Parts involved
- Coolant Bypass Valve A
- Position Sensor
P26A9 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.