This bulletin applies to 2019-2022 Ram 2500/3500/4500/5500 trucks equipped with a 6.7L Cummins Turbo Diesel engine.
The MIL may be on with DTC P203E-00 (reductant level sensor 1 circuit intermittent erratic) set. Repeated freeze/thaw cycles of the urea tank may cause solid DEF crystals to form and settle on the focus tube, blocking the level sensor signal. Rapid temperature sings from below freezing to above freezing may cause an incomplete thaw of the DEF tank. When the vehicle is powered on, the diagnostic is enabled due to thawed DEF at the tank bottom surface, but the fluid in the center may still be partially frozen. This may be caused by the customer over-filling the DEF tank.
Photo courtesy of Mitchell 1
Grade vent valve (GVV).
Chrysler says that replacing the urea delivery module and grade vent valve (GVV) and updating the dosing control unit (DCU) software provides the fix.
Remove the DEF tank. Loosen the hose clamp on the GVV hose and remove the GVV from the DEF tank. Install the new GVV. Replace the urea delivery module with the kit P/N 68457124AD. Install the DEF tank. Refill the DEF tank to specification.
Reprogram the DCU with the latest software and clear any DTCs.
PART PART NUMBER Urea delivery module service kit........68457124AD Grade vent valve............................... 68621194AA DEF 1 gallon..................................... 68035704AC
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