I was cleaning an EM, Gottlieb, Star Trek (1971), for a customer, and I ran in to a bit of a pickle. I am not well versed in the EM world, and as such, I am begging the gods of the EM repair to help me figure the issue out.

When I started everything, the game worked fine, and just needed a cleaning, and rubbering, etc.

I turned the game off and started swapping out all of the bulbs, which I made sure to do with the power OFF! Once I had all the new bulbs in (LED ... I know, Iknow, but it's what he wanted), I turned the power on and the bulbs in the head were fine, but the PLAYFIELD lamps were really, really dim (almost unnamable that they were on). I started a game and the PF lamps immediately dimmed and went off.

I thought that maybe the LEDs were causing an issue, so I put all incandescent bulbs (I checked that they all worked before putting them in). Nothing. I found the 10amp fuse for the PF lamps was blown, so I replaced it. PF lights are on again, but again nearly unnamable they are on. Start a game, pop, fuse blows. I look everywhere, and nothing seems loose or touching. I keep touching various wires and replacing the fuse and ... POP. again and again.

The odd thing is that the rest of the game is working PERFECTLY. The game plays, all of the PF switches/targets work, register, score, etc. The game zero's fine, and the backbox lamps are working perfect.

So, basically, everything, aside from the PF lamps, is working.

Please, please, please, help.

I can post the wiring diagram if needed, as it was folded up in the bottom of the game.

the attached pic is of the area the fuse was that keeps popping. It is the 10amp one in the MIDDLE (fuse is removed in the pic)

thanks,
--ed

IMG_7621.JPG

thanks leckmeck.

Just to confirm, when you say "leaf", you mean the two small tabs that are at the base of the socket, or do you mean the "S" arm that the socket sits on and that connects to the PF?

thanks a million kajillion!

--Ed

DirtFlipper: perfect... thanks! I will check that out. I bet that is the case, as I moved a few down when installing the bulbs from the underside.

u2sean: oh man, that stinks! I know that such things can happen when changing bulbs with the power on, which is why I made sure to turn the game off while installing -- especially since it isn't my game, it belongs to a customer. I am hoping that the fact that it is an EM, I didn't do any major damage, such as your blowing the transistor board. I guess that the same thing that makes EM a pain is the same that make them good -- no "boards" -- lol

Toyguy: good question ... I don't know. I can test it this week and let you know. If it does/doesn't, what is it indicating?

Thanks a million, again, to all who have (and still may) send ANY advice/info my way!
--Ed

Ok, so i went back and checked every socket, and removed all the bulbs from the PF. Still no luck.

I did notice that if i put LEDs in some sockets, and hit a pop bumper or something, i could get the bulbs to flash as the bumper actuated..but they wouldnt stay on no matter what i tried.

Does the fact that the lamps will flicker on than off with something like a pop bumper "thump" help with tracing anything?

Woah! I think you are on to something ith the coin door suggestion! tell me more about the coin door! I was messing with the coin door and found that somebody had previously cut some wires in there and i took the electric tape off, twisted the wires back togethwr, and got the short to stop blowing the fuse. Now it is down to just the lights not going on, instead of the lights going on dimmly and then blowing the fuse a few seconds later.