Reductant Level Sensor
Reports how much reductant is in the tank, and is trusted with more than a gauge reading. The module compares the level falling against the dose it commanded — that comparison is how the system detects a leak, a blocked injector, or a device fitted to defeat the emissions system. So a level sensor that lies breaks several other checks at once.
It is usually part of a combined tank unit measuring level, temperature and often fluid quality together, which is worth knowing before ordering parts: if all three channels are implausible, the fault is the assembly or its connector rather than three separate sensors.
Before replacing it, consider that the reading may be honest. A level that never drops points at an injector not dosing; a level falling faster than commanded points at a leak — and reductant dries to an unmistakable white crystalline crust, so a minute spent looking under the vehicle either finds the fault or rules out the easiest cause.
Also known as: adblue level sensor, def level sensor, urea level sender, reductant level sender, scr level sensor
Referenced by 23 codes
Codes involving this component (23)
- P203F Reductant Level Too Low High
- P20F4 Reductant Consumption Too Low High
- P20F5 Reductant Consumption Too High High
- P203B Reductant Level Sensor A Circuit Range/Performance Moderate
- P203E Reductant Level Sensor A Circuit Intermittent/Erratic Moderate
- P203A Reductant Level Sensor A Circuit
- P203C Reductant Level Sensor A Circuit Low
- P203D Reductant Level Sensor A Circuit High
- P21A8 Reductant Level Sensor B Circuit
- P21A9 Reductant Level Sensor B Circuit Range/Performance
- P21AA Reductant Level Sensor B Circuit Low
- P21AB Reductant Level Sensor B Circuit High
- P21AC Reductant Level Sensor B Circuit Intermittent/Erratic
- P21AD Reductant Level Sensor C Circuit
- P21AE Reductant Level Sensor C Circuit Range/Performance
- P21AF Reductant Level Sensor C Circuit Low
- P21B0 Reductant Level Sensor C Circuit High
- P21B1 Reductant Level Sensor C Circuit Intermittent/Erratic
- P21C5 Reductant Level Sensor A Stuck
- P21C6 Reductant Level Sensor B Stuck
- U0619 Lost Communication With Reductant Level Sensor A
- U061A Lost Communication With Reductant Level Sensor B
- U061B Lost Communication With Reductant Level Sensor C
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- 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
- 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
Information, not instruction
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