Code result
P24FF
Reductant Temperature Too High
Moderate severity
What it means
The temperature of the AdBlue/DEF in the dosing system exceeds the safe limit — risk of thermal decomposition (NH3/biuret formation) and clogged dosing nozzles. Often caused by a stuck-on tank heater, a stalled coolant return or proximity to a hot exhaust component.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Tank heater stuck on
highOne of the most commonly reported causes for this code — check this first.
Heat soak from exhaust or engine bay
mediumA plausible cause — test and verify before replacing parts.
Related help
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