Code result
P246F
Reductant System Cold Start Performance
Moderate severity
What it means
At cold start the SCR system is unable to begin reductant dosing within the required time. Typical cause on diesel cars in winter — frozen AdBlue in the tank or lines, failed tank heater, or a slow-warming SCR catalyst.
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
AdBlue frozen — tank or line heater not working
highOne of the most commonly reported causes for this code — check this first.
SCR catalyst slow to reach light-off
mediumA plausible cause — test and verify before replacing parts.
Related help
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