Powertrain
generic / SAE
P204A
Reductant Pressure Sensor Circuit
A general electrical fault is reported on the DEF system pressure sensor — used to verify pump priming, line pressure, and to detect leaks via pressure-decay tests.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 4A
Possible causes
- Sensor 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: 100–700 €
- Estimated time: 0.7–2.5 h
- Component: reductant pressure sensor
- Component: reductant supply line
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012