Gottlieb SS Mars God of War (Gottlieb, 1981) Gottlieb System 80 (God of switch matrix problems!)

[dustyrhodes92806]

Ok so I have finally inherited a Mars God of War from a friend who won in it in a win a pin tournament. It has been sitting in his garage for 3+ years and never played. There was a new Rotten Dog power supply and MPU board on it before it sat. When I got the machine I order a new Rotten Dog Driver board because it was relatively inexpensive and the original was very burned up and I would get the knock when turning on the machine sometimes. Good news no more knock and all the solenoids are working in the test mode. All lights and sound work, voice was a little intermented but I replaced the A6J1 connector with a new one from Docent Electronics and now that's working nearly every time I turn on the machine.

the machine would intermittently work and spit the ball out and play but string 3 has never worked on the switch matrix, so multi ball would never work. I thought I would replace any bad diodes on the bottom playfield and I found 2 of them . That didn't work and still intermittent on spitting the ball out and string 3 is still not responding

So I just replaced the A1J6 Connector from Docent Electronics and that didn't work, and worse still the ball won't spit out at all anymore. (but I just installed the connector today. It has only spit the ball out and play like 5 times since I got the machine)

I uploaded some pictures. one of them is when the ball won't spit out at all. In test mode these are all the working switches in light green

the other photo is when it does spit the ball out and play the switches are not working are in light red

I think it might be the MPU board because the 2 little led lights on the board are not nearly as bright as the led lights on the Power Supply board and the Driver board, but not sure don't want to try another board till I posted it here. Thank y'all so much in advance and any help will be greatly appreciated.

@pinballdaveh

 

[dustyrhodes92806]

Good news I figured out all my switch matrix issues!!!!!!!!!!!!!!!!!
it was a rookie mistake. The original rotten dog MPU board was put in back in 2020 so I thought there was no way there would be any corrosion on that board. However, I was obviously wrong. I took the board off just to test to see if my connection job was good when doing that, I found some really bad corrosion, So I simply hit that with my fiberglass pencil and the rest is history.
you can see in the picture
Fixed all my switch matrix problems!

Be on watch for corrosion on Rotten Dog Boards, no matter how new they are.

-only issues that remain
1) are a slightly intermittent sound board.
2) background sound does not stop after game over (it just keeps playing)
3) my tube led lights stoped working

@pinballdaveh