A Hyster with a Monotrol is is wired different than the schematic in the GE manual because it uses just the one directional switch that has one circuit NC and one NO. That's what the 7-1 wires on L5 are doing. L5 is the circuit that turns on the card. A Hyster schematic would sure help. I would check to see if you are loosing + battery voltage at L5 when it acts up.
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