P2AFF
Engine Coolant Temperature Sensor 4 Circuit High
Voltage on the engine coolant temperature 4 sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
Voltage on the engine coolant temperature 4 sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
Common causes
- high
Signal wire shorted to B+
One of the most commonly reported causes for this code — check this first.
Typical part cost: $60-280
- medium
Open sensor
A plausible cause — test and verify before replacing parts.
Typical part cost: $60-280
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P2AFF mean?
P2AFF means "Engine Coolant Temperature Sensor 4 Circuit High". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2AFF?
signal wire shorted to b+; open sensor; connector pins corroded - high contact resistance — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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