Powertrain
generic / SAE
P202A
Reductant Tank Heater Control Circuit/Open
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.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 2A
Possible causes
- Heater element winding open high
- Open wire between PCM and heater medium
- Pin pushed back out of connector body low
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 80–700 €
- Estimated time: 0.7–2.5 h
- Component: reductant tank heater
- Component: reductant tank harness
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012