# P203B on the 2016 Ram 4500

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

## Bulletins for this model year that name P203B

- [10219909](https://open.wenmarpro.com/bulletins/10219909), 2022-09-15: Flash: Dosing Control Unit \(DCU\) Diagnostic and System Improvements This bulletin involves reprogramming the DCU with the latest available software and if necessary replacing the unit. Some customers may experience a Malfunction Indicator Lamp \(MIL\) illumination. Upon further investigation, a technician may find the following Diagnostic Trouble Codes \(DTCs\):P207F \- Reductant Quality Performance. P202C \- Reductant Tank Heater Control Circuit High. P203B \- Reductant Level Sensor 1 Circuit Performance.
- [10217578](https://open.wenmarpro.com/bulletins/10217578), 2022-08-08: Flash: Dosing Control Unit \(DCU\) Diagnostic And System Improvements This bulletin involves reprogramming the DCU with the latest available software and if necessary replacing the unit. Some customers may experience a Malfunction Indicator Lamp \(MIL\) illumination. Upon further investigation, a technician may find the following Diagnostic Trouble Codes \(DTCs\): P207F \- Reductant Quality Performance. P202C \- Reductant Tank Heater Control Circuit High. P203B \- Reductant Level Sensor 1 Circuit Performance.
- [10140046](https://open.wenmarpro.com/bulletins/10140046), 2018-06-11: Flash: Dosing Control Unit \(DCU\) Diagnostic And System Improvements This bulletin involves reprogramming the DCU with the latest available software and if necessary replacing the unit. Some customers may experience a Malfunction Indicator Lamp \(MIL\) illumination. Upon further investigation, a technician may find the following Diagnostic Trouble Codes \(DTCs\): P207F \- Reductant Quality Performance. P202C \- Reductant Tank Heater Control Circuit High. P203B \- Reductant Level Sensor 1 Circuit Performance.
- [10138931](https://open.wenmarpro.com/bulletins/10138931), 2018-06-04: Flash: Dosing Control Unit \(DCU\) Diagnostic and System Improvements This bulletin involves reprogramming the DCU with the latest available software and if necessary replacing the unit. Some customers may experience a Malfunction Indicator Lamp \(MIL\) illumination. Upon further investigation, a technician may find the following Diagnostic Trouble Codes \(DTCs\):P207F \- Reductant Quality Performance. P202C \- Reductant Tank Heater Control Circuit High. P203B \- Reductant Level Sensor 1 Circuit Performance.