P24F3Reductant Tank Temperature/Fuel Temperature Correlation
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P24F3 sets the temperature reported from the DEF (reductant) tank against the fuel temperature. After a long soak both liquids rest close to ambient, so a clear mismatch exposes a sensor that reads wrong although each signal may be electrically valid. No manufacturer explains P24F3 in a public service document. Ford's 2023 diesel summary shows the same principle with other partners: P205B flags more than 40 °C between tank and DEF quality sensor temperature at start-up, and P0181 holds fuel temperature against the charge-air reading after six hours off. CARB requires such rationality checks for input sensors that feed emission controls. Where the DEF sensor is built into the tank module, the fix can mean a costly tank unit; driving is normally unaffected.
- What you may notice
- Warning lamp, often after a cold start
- DEF tank and fuel temperature far apart in live data after an overnight stop
- Likely causes
- LikelyDEF tank temperature sensor (often integrated in the tank or sender module) reading wrong
- PossibleFuel temperature sensor drifting
- RareLocal heat source such as an exhaust leak warming one sensor
- RareContact resistance in a sensor connector
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €120 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.