Quoted from jdemarti:
I am having the same problem, but my segment E is out on players 3 and 4. I swapped out IC8 BCD to 7 segment decoder, the IS10 Segment drive for player 3 and 4, and the resistor for the segment. still not working. I also know that the player 3 and 4 slave displays are good as I swapped them with 1 and 2. same segment is out. Also checked the wires, traces, etc. I am out of ideas. Could it be anything in the MPU that could cause a segment to be out? Thanks
Nothing on the MPU can cause a segment to be out. The MPU can cause a digit to be blank, a specific number not appear but it cannot cause a segment not light properly.
Put the game on display test. Use a meter or logic probe to test pin 11 of IC8 to see if it is pulsing when a number with the c segment is displayed. If it is, keep looking. If it does not, IC8 is bad.
Still on display test - probe pin 6 of IC10. If it is, keep looking. If not, check the trace, sockets, etc to see where the signal is being lost between IC8 and IC10.
Still on display test - set your meter to 200V DC. One lead on ground, other on pin 13 of IC10. Be VERY careful not to short pins together or touch the pins with your fingers, there is -100V there. If you see voltage pulsing to near -100V here, keep looking. If not, replace IC10 or look for socket problems.
Still on display test and your meter to 200V DC. One lead on ground, the other on each side of R10. If you don't see voltage pulsing to near -100V here check the traces, solder joints and/or the resistor for breaks in the circuit.