Powertrain
generic / SAE
P24EB
NH3 Sensor Supply Voltage Circuit Low
The NH3 slip sensor supply voltage drops below the lower limit. Usually a partial short to ground in the supply line, an undersized ground path with high resistance, or an internal supply collapse in the SCR/dosing module. Sensor output is held invalid until the supply recovers.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / EB
Possible causes
- Supply line shorted to ground high
- High-resistance ground at the SCR module medium
- Connector pins corroded - high contact resistance low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 120–700 €
- Estimated time: 0.5–2 h
- Component: nh3 sensor
- Component: supply wiring
- Component: dosing module
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012