P24FFReductant Temperature Too High
- 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
- P24FF signals that the diesel exhaust fluid itself has become too hot while the engine runs. The controller reads the DEF temperature sensor in the tank and flags a value above its limit during operation; hot urea solution ages faster and can form deposits. Deutz lists P24FF-00 in its EMR L1 secondary ECU code table (SPN 4337, FMI 11) as AdBlue overtemperature in operation, kept apart from its own warning and critical overtemperature codes. Volvo truck solution KC-10 names a typical hardware cause: when guided diagnostics finds the valve working yet the DEF is confirmed hot, the coolant solenoid valve that heats the tank may be fitted against its flow arrow; turning the valve body around fixes it. Sensor circuit faults are P205A to P205D.
- What you may notice
- Warning lamp with SCR or DEF message
- DEF tank temperature far above ambient in live data
- Likely causes
- LikelyDEF tank coolant solenoid valve installed against its flow direction (Volvo)
- PossibleTank heating valve stuck open so hot coolant keeps flowing
- RareMissing heat shield or exhaust leak warming the tank or lines
- RareDEF temperature sensor reading too high
- 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: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.