Powertrain
generic / SAE
P248A
Reductant Heater A Sense Circuit Low
The sense feedback line for the AdBlue heater A measures voltage below the plausible range - typically a short to ground or open in the heater element.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 8A
Possible causes
- Sense line shorted to ground high
- Connector pins corroded - high contact resistance low
- Harness chafing through insulation 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: 200–700 €
- Estimated time: 1–3 h
- Component: reductant heater a
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012