Code result
P2CF2
Auxiliary Thermostat B Stuck Closed
Moderate severity
What it means
The auxiliary thermostat B is stuck closed. Coolant cannot flow through the affected branch, risking overheating in the bypassed path.
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
Thermostat element failed
highOne of the most commonly reported causes for this code — check this first.
Wax pellet aged - element non-responsive
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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