Quoted from CoinGuyNinja:Nevermind about the wht/red wire, found the answer here.
https://pinside.com/pinball/forum/topic/black-knight-clubmembers-only/page/4
Now about the transistor not firing although it tested good, what should I do next? Pull the driver board and look at traces?
There are several connectors in the path from the driver board to that coil on BK. You need to check.
The first is at the driver board - check for cold solder joints on the header pins and lose IDC connection
Then the connector between the batckbox and cabinet. Check for lose pins, corrosion, bad crimps, etc
Then the connector between the upper and lower play fields. Same things to check as above