bronco71 is on the right track. You have an open circuit for the "up" wire. The bow's trim switch is wired in parallel with the shifter's trim switch. With UP not working on both (where the chance of both failing simultaneously being remote) that would mean there's an issue between the shifter's switch and the trim relays. I forget whether the up trim wire is the blue or the green one of the pair. Those wires could be striped with white as well, depending on the builder's standard.