Quoted from Spybryon:Good idea to narrow down the display causing the problem.
I disconnected player 3 display, and then R11 stopped burning up.
I have the rest of the displays connected now (P1,P2, and P4). On those displays, they work except for segment "d" is stuck on all the time. Segment "d" is the lowest horizontal segment.
On every single display or just 3 and 4? R11 is involved with Segment "d", the lowest most horizontal segment for players 3 and 4. The display issue may have damaged the master display board.
How advanced are you in testing? The 4543 chips are decoders. There are four inputs and a bunch of outputs pulsing at logic level (5v) to turn on the displays. Segment "d" output is p12 at both 4543 decoders. With the game in display test, check pulses there and compare them to the other segments. Check the four inputs to the decoders as well for pulsing(open connector if not). If everything looks good there, replace the UDN IC. If you have a dead output replace the 4543 chip (or lift a leg and check again). The UDN chips take the logic level inputs and ramp them up to high voltage to drive the displays. You can do more checking at the high voltage UDN chips, but it is hard to recommend probing around 100v in tight quarters.