The voltage supplied to the unit is one thing we are working on. Check all your connections, and do check the fuse if you have one. There may be issues on older boats where corrosion reduces the current flow and they have a loss of amperage. Try a direct link to the battery with some wire leads from the terminal block, just run it over the deck to figure out if that has the loss of voltage. Once you do, then you can figure out if it is the wires or a connection perhaps. BCB
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