Like jake said, you can make a jumper to run from a switched source to the 12 volt power wire on the side of the motor. I believe it was the bottom blade on my plug, but not sure without looking at a schematic. I thought my problem was the switch, but it turned out to be a bad motor.

You can also remove the plug on the back of the switch and make a jumper from the black wire to either of the others and the motor should come on with the key turned to the on position.