Cause
Crystallised reductant deposits
Diesel exhaust fluid dried to a hard white solid around the injector and in the pipework. It blocks rather than wears, so the fault is a delivery failure on components that are otherwise perfectly good — and the deposits return unless whatever let the fluid dry, usually incomplete purging at shutdown, is addressed.
Typically specialist work. Needs equipment or training most home workshops do not have.
Codes this can cause (21)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2038 Reductant Injection Air Pressure Sensor A Circuit Range/Performance Likely for this code Moderate
- P203E Reductant Level Sensor A Circuit Intermittent/Erratic Likely for this code Moderate
- P2047 Reductant Injection Valve Circuit/Open Bank 1 Unit 1 Likely for this code High
- P2050 Reductant Injection Valve Circuit/Open Bank 2 Unit 1 Likely for this code High
- P2053 Reductant Injection Valve Circuit/Open Bank 1 Unit 2 Likely for this code High
- P2201 NOx Sensor Circuit Range/Performance Bank 1 Sensor 1 Likely for this code High
- P2214 NOx Sensor Circuit Range/Performance Bank 2 Likely for this code High
- P2BA8 NOx Exceedence - Interruption of Reagent Dosing Activity Likely for this code High
- P2BAA NOx Exceedence - Low Reagent Consumption Likely for this code High
- P2037 Reductant Injection Air Pressure Sensor A Circuit Moderate
- P203B Reductant Level Sensor A Circuit Range/Performance Moderate
- P2041 Reductant Injection Air Pressure Sensor A Circuit Intermittent Moderate
- P2056 Reductant Injection Valve Circuit/Open Bank 2 Unit 2 High
- P207F Reductant Quality Performance High
- P2AD6 Reductant Pump Motor Position Sensor Circuit High
- P2AD7 Reductant Pump Motor Position Sensor Circuit Range/Performance High
- P2AD8 Reductant Pump Motor Position Sensor Circuit Low High
- P2AD9 Reductant Pump Motor Position Sensor Circuit High High
- P2BAD NOx Exceedence - Root Cause Unknown High
- P2BAF NOx System Driver Inducement Active High
- P2BA9 NOx Exceedence - Insufficient Reagent Quality High
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