Skip to content
Book on WhatsApp

P202E

Reductant Injection Valve Circuit Range/Performance (Bank 1 Unit 1)

Reductant Injection Valve Circuit Range/Performance (Bank 1 Unit 1): the signal is implausible or outside the valid range. This valve doses reductant (DEF/AdBlue) into the exhaust for SCR NOx reduction.

  • 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.

  • DEF crystallisation in nozzleCommon
  • Sensor element aged beyond calibration windowLess likely
  • Sensor mounting loose - signal dampingLess likely

Parts involved

  • Reductant Injection Valve
  • Reductant Metering Unit

P202E 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.