Code result
P202A
Reductant Tank Heater Control Circuit/Open
Moderate severity
What it means
The DEF tank heater control circuit is open or has lost continuity — the PCM cannot drive the resistive heater that prevents the DEF (urea) tank from freezing in winter.
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 winding open
highOne of the most commonly reported causes for this code — check this first.
Open wire between PCM and heater
mediumA plausible cause — test and verify before replacing parts.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Related help
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