OBD-II code · Powertrain (generic, extended)

P26AA Engine Coolant Bypass Valve A Position Sensor Maximum Stop Performance

During self-calibration the bypass valve A position sensor never reached the maximum mechanical stop.

Is it safe to drive with P26AA?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySediment prevents valve from reaching maximum stop
  • PossibleSensor not aligned with valve shaft

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
1–3.5 h
Emissions test
Usually unaffected
Parts involved
Coolant Bypass Valve A, Position Sensor

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.