Code result
P2C39
Cylinder Head Temperature Sensor B Range/Performance
Moderate severity
What it means
The ECM detects a range/performance fault on the cylinder head temperature sensor b. Reading cannot be used reliably for control.
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 characteristic drifted
highOne of the most commonly reported causes for this code — check this first.
Sensor mounting displaced
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
Get the full diagnosis
Add your vehicle and see step-by-step repair help, recalls, and TSBs in Wrenchify.
Diagnose P2C39 freeNo credit card required