Quoted from ant68:Yep ! start with replacing the cable that leads to the Cannon , I changed mine and it's all good now .
Re-calibrate the cannon and your in business , If it doesn't calibrate check the proximity switch under the cannon .
I would first test the two switches, as is one is not working, that would do it. There is a home, and one other, but I forget what that one is called at the moment, but it aligns with just above the top target.
You can go into the gun test, and it will move, and should visibly show when the switches are activating. If the home is not working there (which it likely won't be), then test to make sure you hear a click and that the arm is being activated - could just be an adjustment on the arm needed. With the PF up in the test, activate the arm of the home switch, does it register?
Then use a DMM and test the switch for continuity when you close the switch - could be a faulty switch. If the switch is fine, then I would look to the cables. You can buzz out both ends of these wires too to check. I had a similar cable issue with my CV ringmaster had.
I would check in that order first though, as if it is a switch issue, you don't want to spend $ on stuff you don't need, especially shipping to where you are