Powertrain
generic / SAE
P20C9
Reductant Control Module Requested MIL Illumination
The dedicated reductant/SCR control module has requested that the master PCM illuminate the malfunction indicator lamp — a generic forward of an internal SCR fault. Read the SCR module subcodes for the actual cause.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / C9
Possible causes
- Internal SCR module fault — read subcodes high
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: hard
- DIY: shop recommended
- Estimated cost: 80–2500 €
- Estimated time: 0.5–6 h
- Component: scr control module
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012