Code result
P20B6
Reductant Metering Unit Heater Control Circuit Performance
Moderate severity
What it means
Metering unit heater is electrically OK but does not warm the block within the expected time — partial winding fault or excessive heat loss.
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
Partial winding fault
highOne of the most commonly reported causes for this code — check this first.
Related help
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