Ok, so I got my unhappy BK working yesterday and I can get a game started from attract mode.
The new problem is that the callouts (when they happen, which is not when they are supposed to), are wrong. There are no callouts when the game is started, when multiball is started and all the other times when there is supposed to be voice. For some of the voice callouts, I get some of the sound effects instead. When a game ends, I get the phrase you would get when you get an extra ball. Most of the callouts are just missing, for example when you hit magnasave and the ball drains, there's no evil laugh at you.
1. MPU test returns the "0"
2. Sound board test button returns the expected sounds - the first four (or five) are sound effects, followed by the vocabulary listed in the diagnostics.
I have one stuck switch, the upper right bank of drop targets, the left side. I haven't fixed that yet, but suspect that switch has been stuck a long time. The rest of the switches test fine. All the solenoids test fine. Not that it's relevant, but the displays all test fine too. All fuses are intact.
Any ideas on this one?