When I attempt to start my Space Mission the lights come on, but that's it. I press the credit button and nothing happens. I checked the four fuses on the panel and they are fine. I have it set to free play and have double checked my jumper. I should mention this is the first start since clear coating the playfield and replacing the bottom board. I've had a lot of things apart and have cleaned switches as I went. The machine was working perfectly before I started the refurb. This is the first time I've worked on an EM and need some help. I have the schematic, but am unfamiliar with them and AC current. One of the things I noticed is I have about 30VAC on both sides of the switch for the credit button without pressing the switch and the contacts aren't touching. That doesn't seem right to me. Where should I start?

I broke out my ohm meter and started tracing the circuit for the credit button switch. I found I had an open circuit for the reset relay switch (E). I cleaned the switch and now have a complete circuit all the way to the EOS switch on the credit unit. I cleaned and adjusted the upper contact on the EOS switch. Now when I hit the credit button the score reels reset, game over light goes out and the ball kicks out into the shooter lane. One hurdle down, but I still have problems. Nothing on the playfield will score a point and the chime coil once activated stays on (load buzzing). I don't have more time tonight, but hope to work on it again tomorrow. Where should I start? Any ideas?

It's been a rather frustrating night. When I tried starting the machine tonight I had lights, but nothing else. I messed around cleaning relays again and it started working with most of the playfield functions except for the kickers. I started cleaning contacts in that circuit and you guessed it, the machine won't start a game again. I went back to the beginning with the ohm meter and while messing with the credit unit coil all of a sudden I got a good circuit and of course the machine started. That time I was able to play an entire ball with everything apparently working including the kickers. The ball drained and of course it still said I was on ball one and it didn't kick out into the shooter lane. I cleaned all the Jones plugs and don't have time until tomorrow to try again. This is getting very frustrating.

Nothing is consistent so far. It doesn't do the same thing twice. Whenever I think I'm making progress it reverts to not starting a game again. I plan to work on it more tonight.

I started tracing the circuit as Fredsmythson suggested. I found high resistance at the Jones plug that leads to the credit button. I untied the string and moved the wires around and suddenly I had a complete circuit from the button to the plug. I hooked it up and still nothing worked I then moved the wires around by the reset relay and still nothing. Then as Rolf_martin suggested I manually closed the coin relay and the game came alive. I played an entire game with everything on the playfield working. Much to my surprise I was able to start another game and have played about 10 games since with a successful start each time. After the second or third game the playfield lights flickered a couple of times and have been out ever since. The lights in the backbox all work with the exception of the same player shoots again light. The coin door lights also don't work. As much as I want the lights to work I'm scared to touch anything for fear it may not work again. Ideas?

I should mention I did check the fuses and they are OK. To add to the story; all the scoring features work including the bonus at the end. I just don't have any lights. How can I tell which circuit goes through which Jones plug? I don't see the plugs on the schematic. I'm thinking I should start at the plugs for the playfield although the coin door is different. The coin mechanism also doesn't work although I don't really care. It did work before.

Update I removed the fuse and found it was open. It is a 15amp, but what type should I install? I ask since I see several different types in the fuse holder.

I checked my amp load and found it was a little over 4 amps. I replaced the fuse and now it works fine. We played several 4 player games tonight and it works great. Thanks to everyone that helped.

Pretty lights

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