After you refill the diesel exhaust fluid on Ford Transit 2015 and newer models, you will need to reset the exhaust fluid range and fluid empty light. This can be done with the latest Snap-on software.
With your scan tool hooked up to the vehicle, select the Engine System, go to Functional Tests then Selective Catalytic Reduction, and select SCR System Refill Activation.
You will need to carry out this procedure after refilling or replacing the reductant tank to activate the Selective Catalytic Reduction System refill detection strategy.
To start the test, make sure the reductant tank is full then set the ignition switch to on and the engine off.
At the next screen, set the ignition switch to off, then leave the ignition key in the off position for three minutes.
You will then get a message stating that the procedure has been successful. The fluid indicators are now properly calibrated.