Open the backbox and with the power off, unplug connectors A1-J5 and A1-J6. Turn the machine back on. If the machine comes to life (flashing lights, etc.) then you have a stuck slam tilt and/or switch shorting. Turn the machine off and check the slam-tilt on the coin door and the roll-ball tilt that these switches are clean and normally closed. Check the coin door switches for shorts. You will have to remove any coin mechanisms to clearly view the coin switches. Note that the coin lockout wires may tangle with the coin switches, shorting them out. Check to see that none of the coin switches are stuck closed. If none of these are a problem you'll have to look elsewhere for a shorted switch. Once you correct the short, reconnect A1-J5 and A1-J6 and turn the machine back on and the machine should come up and be ready for play.