Finishing up a restore on my STTNG and I am having trouble with both gun Optos. On the right gun the Opto is registering as a square in the switch test however when I block the beam it rapidly bounces from open to close? The left gun opto is not showing as a blank square in switch test and is not working. When I shine a flashlight it does register. There is 13 volts present on both. I replaced all Opto with new ones and it did not help. Also checked CPU board and not ground issue. All other Optos in the game work good. Help!

I did not replace the harnesses. I will wiggle them and see what I get. Why would it open and close rapidly when nothing is moving?

I will run some temp jumpers and see what I get.

I wiggled the wire harness and it opened and closed the Opto switch so that tells me it must be breaking and making a bad connection. I am guessing the left one might be bad too. I think I will buy new harnesses.

I replaced both harnesses with new harnesses and I still have the exact same issues. Any other ideas?

Help!

When I play a game the left launcher runs constantly and the display keeps saying pull trigger to launch ball. In other words it thinks there is a ball loaded in the left launcher. When I pull the trigger the coil does not fire either. It does fire in selenoid test mode though.

yes I reflowed the Opto.