Code result
P26A5
Engine Coolant Bypass Valve A Position Sensor Circuit Range/Performance
Moderate severity
What it means
The bypass valve A position sensor reading does not correlate with commanded position. Sensor drift or worn linkage.
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
Sensor signal drift after thermal aging
mediumA plausible cause — test and verify before replacing parts.
Worn linkage between actuator and valve
mediumA plausible cause — test and verify before replacing parts.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Related help
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