Hi everyone, I need help with a Black Knight.

Machine is a friends that I am doing a play field restore on. Machine was having trouble booting into attract at his house, but when I moved it to my house now it wont boot at all.
All playfield connectors were removed and reconnected at my place.

I only get the Gen illumination to come on with power switch. No displays, no feature lights.
CPU light on board will mostly be a zero, sometimes it does not even come on.

Seems really flaky, when powered on I hear the speaker buzz then fade out. Sometimes a random sound effect will fire off. Sound board test still seems to work fine though.

after futzing with resetting connectors, 40 pin etc, I got some activity but just a flash of response from displays then they are out, zero on cpu board.

Boards were recently sent out and repaired, I am stumped on this one and really bummed as its not my machine.

Anybody have any advice for why its not booting? where should I look to next?

Thanks!

Thanks for the suggestions so far. Play field was hooked up incorrectly once before by the owner, that is what prompted the initial board repair.

It honestly seems to act like that is the issue!, but we marked each of the connectors before taking it apart. So I ma pretty sure they are correct. I have checked and double checked this many times. The two that can be interchanged, one is white and one is black, wire colors are matching as are marks made before disconnection.

I will check the power going to the cpu side tonight. Is the procedure for that to test the connectors while installed?

Thanks

To close this out. This issue looks to have been something as simple as replacing the batteries! I guess the cmos memory is not holding a charge? I did a few simple things to troubleshoot, but I believe replacing the batteries allowed the machine to once again boot.
Thanks for the help!