I'm having an issue with my EBD. Suddenly, the ball ejector switch has stopped working along with my 2X-5X drop targets. I did a solenoid and they all fire and the switch test shows 0. Any ideas what would cause this?

I have checked every switch and there are no loose or broken wires. My credit and tilt switches are working.

I did as you said and traced it all the way to the MPU and discovered the wire had come loose from the plug. I slipped it in and crimped it...all fixed! Thank you all very much!!