I'm working on a Solar Ride and am having some troubles with coils firing on boot.
The machine resets correctly however before showing the displays, both out kicker coils fire in sequence. They do not lock on, just one fires then right after, the second one fires.
The credits reads "72" and the ball-in-play reads "70".
Upon starting a game, one of the kickers fires every few seconds and scores the appropriate number of points. It continues to do this until I shut the machine down. All other switches do appear to register points as well if I hit them.
If I start a game without the driver board connected, the points are still scored over and over which points to the mpu.
To confirm that the mpu was the issue, I've installed a good working replacement and the game plays as expected, with no coil fire on boot.
If I remove the game PROM the coils no longer fire on boot but of course I can't play the game at that point.
Upon running the 13th diagnostic, everything appears to fire as expected however switches 30-35 and 40-44 are detected as closed.
Diagnostics 1, 3, 4, 5, 7, 8, 9, 10 all show garbled numbers. However all displays check out in diagnostics 11 and 12.
I have done all ground mods, bypassed the tilt, and replaced a bad inverter at Z9. I have also tested Z29, Z27, Z8, Z28, Z6, and Z7.
I have swapped out U4 from another board with the same results.
All pulses are correct on TC1.
If someone could perhaps point me toward a test point, that would be great.