Powertrain
generic / SAE
P2042
Reductant Temperature Sensor A Circuit
A general electrical fault is reported on reductant (DEF) temperature sensor A — used to compensate dosing for fluid viscosity and to enable tank heating in winter.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 42
Possible causes
- Sensor element failed high
- Harness fault medium
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: 80–600 €
- Estimated time: 0.7–2.5 h
- Component: reductant temperature sensor
- Component: reductant tank
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012