P20FE
Reductant Metering Unit 1 Performance
The first DEF metering unit (the integrated module that combines pump, filter, level sensor, and dosing valve) is electrically OK but does not deliver the expected pressure or flow during operation.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
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)
Common causes
Ordered by how often each turns out to be the cause.
- Metering unit aged or partially cloggedCommon
Parts involved
- Reductant Metering Unit
P20FE is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.