Powertrain
generic / SAE
P201A
Reductant Injection Valve Circuit Range/Performance (Bank 2 Unit 1)
The DEF (urea) injection valve on bank 2, unit 1 does not respond to commands within the expected range — flow or response time off-spec, no obvious electrical fault.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 1A
Possible causes
- DEF crystallisation clogs the dosing nozzle high
- DEF supply pressure below target medium
- Valve coil ageing — slow response 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: hard
- DIY: shop recommended
- Estimated cost: 150–1200 €
- Estimated time: 1–4 h
- Component: reductant injection valve
- Component: reductant metering unit
- Component: scr catalyst
- MIL / check engine light
- emissions-relevant
- limp mode possible
Sources
References
sae:J2012