Quoted from Brewer12:
I'm new with the repair of my Laser war pinball machine. It won't let me reset a new free play. It displays "missing ball" even though all 3 balls are in the machine. Any suggestions.
You might want to start your own thread, so you can get views specific to your issue. But in the meantime....
If you don't have a manual, here is a link to it:
Remove the balls from your game.
Page 14 gives instructions on how to enter game diagnostics. The FORWARD/REVERSE button should be the one that you can click "down" then unclick "up" (like a ballpoint pen) and it should be in the middle (if you have three buttons). Setting it to "down" is the same as "reverse". So set it to "down" then hit the STEP button (Which I think is the one farthest from the coin door) until you get to SWITCH TEST. In SWITCH TEST, any switches that are "active" will be displayed on the Player 1 & Player 2 display (switch title), as well as the Ball In Play display (switch number).
On page 17 there is a diagram of the switch matrix and on page 18 there is an image of where those switches are located on the playfield. Manually press switch #52: Shooter Lane and see if it is noted on the display. Repeat that process for switches 10-12: Ball Trough 1-3. Any switch that doesn't display when you manually press it needs to be addressed.
My guess is that one of your trough switches is bad (broken wire, bad switch, etc.).