Reductant Injector
Meters urea solution into the exhaust so selective catalytic reduction can convert oxides of nitrogen into nitrogen and water. Its characteristic failure is crystallisation: urea that is not fully atomised leaves a hard white deposit that builds on the injector tip and inside the pipe until nothing passes. That damage is cumulative and largely preventable, which is why a dosing fault is worth catching early — the same fault left alone becomes a blocked injector, a crystallised line, and eventually a vehicle that will not run, since these systems are required by law to restrict operation when they cannot dose.
Also known as: adblue injector, def injector, urea injector, scr injector, reductant dosing valve, dosing module
Referenced by 107 codes
Codes involving this component (107)
- P241D SCR Inducement - Forced Engine Shutdown Stop driving Critical
- P2047 Reductant Injection Valve Circuit/Open Bank 1 Unit 1 High
- P2048 Reductant Injection Valve Circuit Low Bank 1 Unit 1 High
- P2049 Reductant Injection Valve Circuit High Bank 1 Unit 1 High
- P2050 Reductant Injection Valve Circuit/Open Bank 2 Unit 1 High
- P2051 Reductant Injection Valve Circuit Low Bank 2 Unit 1 High
- P2052 Reductant Injection Valve Circuit High Bank 2 Unit 1 High
- P2053 Reductant Injection Valve Circuit/Open Bank 1 Unit 2 High
- P2054 Reductant Injection Valve Circuit Low Bank 1 Unit 2 High
- P2055 Reductant Injection Valve Circuit High Bank 1 Unit 2 High
- P2056 Reductant Injection Valve Circuit/Open Bank 2 Unit 2 High
- P2057 Reductant Injection Valve Circuit Low Bank 2 Unit 2 High
- P2058 Reductant Injection Valve Circuit High Bank 2 Unit 2 High
- P208B Reductant Pump A Control Performance/Stuck Off High
- P208E Reductant Injection Valve Stuck Closed Bank 1 Unit 1 High
- P20E8 Reductant Pressure Too Low High
- P20E9 Reductant Pressure Too High High
- P20EE SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 1 High
- P20F4 Reductant Consumption Too Low High
- P20F5 Reductant Consumption Too High High
- P20F6 Reductant Injection Valve Stuck Open Bank 1 Unit 1 High
- P20FB Reductant Pump B Control Performance/Stuck Off High
- P218F Reductant No Flow Detected High
- P2200 NOx Sensor Circuit Bank 1 Sensor 1 High
- P2201 NOx Sensor Circuit Range/Performance Bank 1 Sensor 1 High
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Exhaust Pressure Control Valve 56
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Secondary Air Injection Pump 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Particulate Matter Sensor 24
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Heater 20
- Catalyst Temperature Sensor 20
- Fuel Filler Cap 18
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
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