Hey guys - Just picked up a non working Buck Rogers today. Game is overall in pretty good shape, but does not boot. When I hit the switch, all I get is GI and the score displays. The ball/match number display does not come on. I have very little experience with these games. What are some things to check for? Here are some things I did and what they showed:
1 - Checked all fuses. A ll tested good. Tested them out of the machine as well to make sure.
2 - seated and reseated all connections. Also ensure all connections were correct. They are all labeled so I am fairly certain they're good to go.
3 - Checked voltages at A2 (power board in back box). The results were a little weird to me. At connector J2, I have +5 and -12. They are adjusted to 5.3 and -12.4 Vdc. When I check the connectors at J3, I get different results if I remove the connector from the board and read voltages at the pins themselves than I do if I plug in the connector at J3 and read the voltages at the back of the connector. Voltages WITH connector connected are 35 (supposed to be 60), 17 (supposed to 42), 4 (supposed to be 4), and 8 (supposed to be 8).

With the connector DISCONNECTED at J3 and reading the pins I get 61 (supposed to be 60), 44 (supposed to be 42), less than 1 (supposed to be 4), less than 1 (supposed to be 8).

A couple of other tidbits.
1 - The battery I am sure leaked on the board sometime. Not badly, but I can see that someone cleaned it up and brushed the board at the edge connector. They also removed the batteries from the game and solder two wires to the MPU and located the batteries offboard. They did NOT use a battery holder. They literally soldered three batteries together and wrapped them in electrical tape and then soldered the wires coming off the pack to the board. I cut the whole mess off. So now there is no battery connected at all.
2 - I metered all traces surrounding and they appear to be fine. All connectors appear fine and I cannot see any corrosion on any connector.
3 - They also soldered/jumpered several of the plugs' ground wires (green/yellow) together. Can't understand why they did this. They literally soldered a piece of wire to each of the ground wires and to each other. I have not yet cut these off, because I haven't pulled the schematic, but I am fairly certain that wire is the ground wire (green/yellow).

Any help would be appreciated. Where should I go now?

OK, reseated all connectors...for a fifth time. This time the game booted. Definitely have some adjustments to do. But still having issues. displays seem to work but when it cycles to show highest game, the displays show gibberish. I will try and upload pics.

Thanks guys. Which connectors should I focus on replacing?

Also, the battery has been removed and I heard that the machine will do wonky stuff if there is no battery in it. So I'm getting a battery holder and diode and going to try that first.

Don't have the larger cap for the power supply but I will do the ground mods to the PS and CPU. Anything else I should do/check?

Repinned the connectors and now it own't boot. Wondering if I pinned the A1J6 connector to the MPU wrong. I don't think I did, as I changed one at a time, but anything is possible. I am getting ready to do the grounding mods. Considering just ordering a new MPU and possibly a new power board. Two questions though - do I still need to do the ground mods with a new MPU and power board? Secondly, should I just recap the power board and do the ground mods vice replacing it?

Symptoms i get now are the startup sounds. GIs are on and the game over lamp is lit. No displays and game does not complete boot. Any thoughts?

I have checked the voltages st C16 and C17 on the MPU. C16 read 5.7vdc which is correct. That said, I only get about 4.8vdc at C17. My understanding is that is supposed to be 12v - correct?

That's what I am saying - my voltage at C17 is not what I think it should be. Is that correct? If so, what should it be and what is likely the cause? Also, one of the things it does as well when you power it on is that it does not boot but puts a ball from the trough to the shooter lane.

I'll have to check. It might be firing all of them. It definitely isn't firing the flippers or sling. I would have noticed it. I do have -12 at the connector to the MPU pcb. Where can I read it on the MPU itself to verify its there?

If it's not there, what could be the problem? Because I am getting -12 to the MPU.

Thank . Found the-12v issue. I had the connector mispinned when I replaced the connectors. Still have issues. Some symptoms:
- Game boots and I can start a game
- plays old and registers for a bit and then basically freezes
- will all of a sudden start running score up and not stop
- ball eject for bonus works fine for a while and then won't eject the ball and score keeps going up. This is often in conjunction with the freezing mentioned above.
- I believe some of the back box lights are supposed to flash. I have no flashing lights anywhere.

Think the mpu might be bad. It had previously had acid damage. You can see where someone tried to clean it up. Anyone in Northern Virginia have one I can borrow?