The short answer is Yes, you can add a switch to make it work. You should use an intrinsically safe switch or remote it far away from the filling station to avoid ignition of the fumes. Make sure you remove power from the circuit before working on it. Working on any electrical circuit in proximity of gas fumes is an explosion hazard with high risk. I am not endorsing this modification….
I went through two of the OEM panels on my 2021 Fuzion before I gave up. At $150 ea, it just wasn’t worth it to me. My remote fuel level gauge never worked since new (even after the dealer “fixed it”) so I don't miss that function. When it was new it always read empty. After it was “fixed” it always reads 100%.
As mentioned above, you will lose the reversing function. Mine reversed the pump to clear the lines AFTER I finished pumping, not before. However, you could use a DPDT switch and wire it so that you could manually run the pump either way. Without the reversing function, you are likely to spill gas that is left in the fill hose while stowing it.
I have the wiring diagram for the unit and will attempt to attach it here. Please note that the two wires IN use red for positive and black for negative. The two wires OUT use black for positive and white for negative.
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