Hello everyone,

this is my first time reaching out. There’s a ton of Brilliant pinball enthusiast on here. So it doesn’t hurt to have a few other brains to help solve this pin trouble.

The pin is Gottlieb System 80 Mars God of War. It’s 99% ready to play ball one. A switch matrix issue is preventing the game from playing.

All game fuses test fine.
Replaced all connectors and pins.
Replaced filter cap and three bridge rectifiers.
Isolation diodes 1N270 test fine.
All solenoids and diodes test fine.
Game boots up fine. 99 shown in the credit display.
Press the replay button then the displays flash waiting on balls. Ball 1 shown in credit display. 3 balls in the though.

Switch matrix test errors:

Close sw34 (right flipper)
Display then shows incorrect numbers
sw31 (#2 Right Drop target)
sw32 (#2 Center drop target)

Close sw44 (Trough):
Display then shows incorrect numbers
Sw41 (#3 Right drop target)
Sw42 (#3 Center drop target)

Close sw54 (Bottom right rollover):
Display then shows incorrect numbers
Sw51 (#4 right drop target)
Sw52 (#4 Center drop target)

Strobe 6 has non-functioning switches:
Sw60 left our lane rollover
Sw61 right war base
Sw62 left war base
Sw63 right launch lane
Sw64 outhole

I attached my drawn out switch matrix issues to help put it all in perspective

Hopefully this can help other system 80 owners too.

Thanks everyone!
Stay healthy and safe at home. It’s not so bad when you have pinball machines.

DF9036DA-F9D6-46C0-9132-DB08438B7C58 (resized).jpeg

I’ll update this pinrepair as soon as I can see the solution in front of my eyes ha!

Thanks YeOldPinPlayer,
I disconnected the playfield and testing the matrix using jumpers directly on the board. Also checked the switch matrix with my logic probe. Did a continuity check on all switches and they all tested fine but one. The problem was the previous owner had soldered the troughs coil leads backwards on the lugs!
Now the game plays like a new machine out of the box. Next up for repairs is a Black Hole, Counterforce, The Amazing Spider-man, Flight 2000, Close Encounters, Pinbot and Fireball 2. Wish me luck ha!