Arcade Collecting > Miscellaneous Arcade Talk

What's Wrong with this Ms. Pac?

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tbombaci:
Gently re-seat the ribbon cable to the daughter PCB. (you will need to remove the Sync Bus card to get to it)

If that doesnt work, gently remove the Z-80 from the daughter card and stick it in the slot where the ribbon cable is plugged into. Re-seat the sync-bus card and turn on the game. If all is good, Pac-Man should boot with odd shaped characters (ghosts and Pac) The game should play as pacman.

If this is the case, the ribbon cable is probably toast. A new cable is about $10.

-Tom

MonitorGuru:
Check this page and compare screen shots:
http://www.arcadegameover.com/troubleshoot/pactrouble1.html

I'd hazzard to guess the following, in order:
1) Bad video ram. Swap (to diagnose) and then replace the 2114/9114 chips in row 4
2) Bad Sync Buss Controller board, pins, socket.
3) Bad Z80-chip, socket
4) For Ms.Pac: Bad daughter cable, sockets (on both ends)

Regarding the video ram: If the chips are TI brand chips (texas logo) be VERY careful. They have the weakest legs and break VERY easily. You may even notice a break with one still in the socket. Press against them and you might just find the offending one without even removing.  All the other brands I've seen (GTE, National Semiconductor, etc...) have much stronger legs in Pac boards and are much easier to swap to diagnose.

sc1103:
Thanks for all the help so far guys...Ill hopefully be goin out there soon to see what I can do and Ill report back

RayB:
Keep in mind that insufficient voltages levels will cause problems that look like bad RAM, etc...

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