IF the motor is still driving the bucket into the stops, according to Joe’s drawing, you possibly have a dual failure...
The ignition switch could have failed first, and the limit switch stopped interrupting power to the down motor when you cycled the lights... all this assumes no one modified any of the wiring.
Not sure where the connections are, but if you can check the output at the down limit switch, while cycling it between limit “off” and “on” (buckets manually up part way, motor disconnected), it might give more clues...
Good luck.
Rocky
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