P2A4B
Alternative Fuel Temperature Sensor Circuit
The AFCM detects a generic fault on the alternative fuel temperature sensor. Fuel viscosity and density compensation cannot be applied reliably.
The AFCM detects a generic fault on the alternative fuel temperature sensor. Fuel viscosity and density compensation cannot be applied reliably.
Common causes
- high
Temperature sensor failed
One of the most commonly reported causes for this code — check this first.
Typical part cost: $60-280
- medium
Wiring or connector fault
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 P2A4B mean?
P2A4B means "Alternative Fuel Temperature Sensor Circuit". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2A4B?
temperature sensor failed; wiring or connector fault — 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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