Code result
P2AFF
Engine Coolant Temperature Sensor 4 Circuit High
Moderate severity
What it means
Voltage on the engine coolant temperature 4 sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
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
Signal wire shorted to B+
highOne of the most commonly reported causes for this code — check this first.
Open sensor
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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