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If the light does not go out when the terminals are jumped, the control board is defective. If the light goes out when the terminals are jumped, the wiring has a break or the limit switch is defective.
Power off the machine. Then, disconnect wires from the switch and tape the end of each wire together to prevent shorts. (disconnect the jumper as well)
Power on the mill.
If the diagnostic light is off, the wiring is OK and the switch is defective.
If the diagnostic light is on, the wiring has a break or defective connection.
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If the light doesn’t go on when the wire is removed, the control board is defective.
If the light goes on when wire is removed, the wiring has a short or the limit switch is defective:
Power off the machine. Then, disconnect wires from the switch and tape the end of each wire together to prevent shorts. Plug wire J2-1 back in.
Power on the machine.
If the diagnostic light is on, the wiring is OK and the switch is defective.
If the diagnostic light is off, the wiring has a short circuit.
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