Check your lamp matrix in the manual, probably on that. If a mechanical switch and not optos, that would be the next thing to check.

LTG : )

Maybe about once every twenty or so games, during boot up, my left cannon will fire and the plunger will stick. When this happens the cannon will not find home. I've cleaned everything and put new coil sleeves in. It seems to happen less often, but it still happens on occasion. And just the slightest touch will send it back to it's place. I don't have a permanent fix, but wanted to let you know I've seen it happen. I haven't done any wire replacement on mine.

Good luck!

I have the same issue with my right cannon and the plunger sticking out but going back in with a little push. It seems to be random on whether it finds home or not. I'm curious if the wiring harness works for you. Keep us updated

Magnetized ?

LTG : )

Cannon_(resized).jpg

Yuck, I should have taken more post restore pics ... don't let your cannon look like this ever.

My OCD kicked in and I had to post a better pic.
IMG_1567_(resized).JPG

The cannon not finding home and continually rotating may have nothing to do with the cannon wiring harness; this is where the pair of micro switches under the playfield come into play. There are diagnostics for the cannons that monitor these two switches.
STTNG_Motor_(resized).jpg

As for the cannon plunger sticking out, it sounds like its binding. Could be a bad sleeve, spring, wire in the way ... any number of things.

here is a much better picture of the cannon home switch, this is from the right cannon.
IMG_1568_(resized).JPG

After giving this some thought ... what is likely happening is that the cannon optos are telling the processor that there is a ball loaded in the cannon, the cannon then rotates to a firing position to expel the ball and fires the solenoid, if the plunger sticks out, the plunger itself is likely blocking the optical path at this point so the cannon continues to rotate thinking there is a ball loaded in the cannon. This can be a problem with the cannon wiring, or an issue with the optics themselves.

It's been a few weeks (lol), any luck?