Powertrain
Definition only
Lights the check engine lamp
P2AFF: Engine Coolant Temperature Sensor 4 Circuit High
Standardized SAE J2012 code · P2Axx codes
What does P2AFF mean?
Voltage on the engine coolant temperature 4 sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Common causes
- High Signal wire shorted to B+
- Medium Open sensor
- Low Connector pins corroded - high contact resistance
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2AFF on the same make and model first.
P2AFF in the community
Ask about P2AFFNo one has posted about P2AFF yet
Share your vehicle, the tool you used and what you tested — the first thread helps everyone who searches for this code.
Describe your P2AFF problem