Code result
P26B1
Engine Coolant Bypass Valve A Stuck Closed
Moderate severity
What it means
The coolant bypass valve A is stuck closed. Coolant cannot bypass the radiator during warm-up so warm-up takes longer and emissions in the warm-up phase rise.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Valve seized closed by debris
highOne of the most commonly reported causes for this code — check this first.
Actuator linkage jammed in closed position
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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