When I picked up this Stars last month the left sling wasn’t working and the flippers needed a rebuild. I decided to work on the flippers and left sling at the same time. Before making it to that point, some friends were over playing and told me Stars was “frozen”. Which is was, along with a burning smell. Determined the right sling coil was burnt so ordered some new coils.

Started to dive in, replaced the right coil, but now it doesn’t fire. Pulled fuse from PF, tested ok. Pulled all fuses in backbox, tested ok. All other game features and coils work, including the switches that score for the slings. Test mode does not fire the coils. I’m guessing I have 2 blown transistors and trying to decipher the schematic is a little tough. I THINK the transistors in question are Q9 and Q11?

NOTE - I also own Bally Eight Ball and Mata Hari, can I swap the driver boards with no ill effects to try and rule things out?

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Swapped in a Bally board, instantly blew the fuse under the PF.

As mentioned in my OP, I need to check the transistors and was having a hard time deciphering the manual, so haven’t tested them yet. Ultimately I can test all of them.

Coil is brand new. Could the diode be bad from factory, yes, but I’m betting against it.