I recently had board work done to my Black Knight. All of the capacitors have been replaced, the 40 pin connector replaced, and resistors. The game was working pretty well for a few days and then I noticed some lights were no longer lit. I turned the machine off and left it at that. The next time I turned on the machine it doesn't do anything but light the GI. I can't go into the test mode. I'm not sure what to do from here.

I unplugged the cable from 1J2 and stuck the black lead of my DMM to pin 1 and test pins 4, 5, & 6 and they were +5v and pin 9 is +12v. When I pulled the cable off the little red IC35 diagnostic display came on. I turned off the machine and plugged the cable back in and the IC35 display does not turn on.

I tested the following Test Points:

TP1 = +13.6v
TP2 = +3.9v
TP3 = +0.3v
TP4 = 0v
TP5 = +4.9v
TP6 = +2.4v
TP7 = +5v
TP8 = +4.9v
TP9 = +5v

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Looks like it might be the SCANBE sockets. I will replace those and report back. I did remove two of the Integrated Circuit chips and put them back in the sockets and the game booted up.