If your Mercedes Sprinter van was not built with the J51 option code for the fuel gauge, a Mercedes-Benz Sprinter dealership will need to add the J51 option to your Sprinter van’s computer (called a VDoc update) via the OBD2 port. This is the same procedure that is required when adding an auxiliary heater to a cargo van being converted to a camper van. Without the J51 option, your Sprinter will not “see” the upgraded S&B Filters extended range fuel tank and it will put you into “limp mode” at approximately 1/2 tank because it thinks you are out of fuel.
The S&B Filters J51 Fuel Sensor Dongle for Mercedes Sprinter Vans (TI1349-00) from Nomadic Supply Company will allow you to add the J51 fuel gauge option to your Sprinter van’s computer yourself without the Mercedes-Benz Sprinter dealership.
Mercedes Sprinter vans that do not have the factory J51 option have a fuel level sensor in the OEM fuel tank, but they use the vehicle trip computer to calculate an estimated fuel level for the instrument cluster fuel gauge. Only when the fuel tank is filled 100% does the internal trip computer reset, and the fuel gauge shows Full.
Mercedes Sprinter vans that do have the factory J51 option also have a fuel level sensor in the OEM fuel tank, but J51 optioned vans use the level sensor to communicate to the fuel level for the instrument cluster fuel gauge. So, when you upgrade your OEM fuel tank to our S&B Filters extended range fuel tank, your fuel gauge will show the correct fuel level.