Code result
P20EC
Reductant Heater "A" Control Stuck Off
Moderate severity
What it means
The reductant tank heater "A" does not heat when commanded on. Either a failed element or a stuck-off driver in the dosing module.
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
Heater element open
highOne of the most commonly reported causes for this code — check this first.
Heater driver stuck off
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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