Garbled screen help-1980 Sega Gremlin space firebird

[JasperQuibbs]

Hello everyone! I'm new to this forum. I recently got a space firebird cocktail from a friend. When I turn on the power the screen just shows random graphics and there's a sound playing on a loop. I've tested the voltages and checked the fuses and everything looks in order. Someone did modify it to coin up with a button but it does nothing. Any ideas?

[alby13]

It sounds like there is an issue with a component or components on the board. You checked the basics well. Time to get a little more advanced. Usually people test a cabinet by swapping out the game for another one that is known working, although I know that can be tough.

[egermanus]

Can you post a picture? Could be anything from bad ram to a broken trace.