Verified and documented hard-to-find information about consumer products, including repair solutions, obsolete parts, replacement part numbers, compatibility, specifications, diagnostics, vintage electronics, appliances, arcade hardware, and other obscure technical knowledge.
Multiple Memory, Socket and Color Faults After Reversing Ms. Pac-Man Modification
Repair Case Summary
This page documents a firsthand Multiple Memory, Socket and Color Faults After Reversing Ms. Pac-Man Modification repair case.
It is intended for technicians and collectors troubleshooting original Pac-Man or Ms. Pac-Man arcade PCB hardware.
Date: 2019-03-15
Board: Original Pac-Man PCB previously modified to play Ms. Pac-Man without daughter card
Category: Boot / memory / color / socket
Symptoms:
After reversing the old Ms. Pac-Man modification, the board would not boot.
After initial memory replacement, further problems remained.
On the diagnostics screen, the dark-blue ghost appeared orange/dark blue and the cherry appeared white.
Diagnostic observations / tests:
ABC Diagnostics found three of four color RAMs at 2A-2D bad and all 2114 scratch memory bad.
After replacing those parts, the sweep holding the 283 was found loose and not making connection.
After replacing the sweep, diagnostics passed except for incorrect colors.
Further investigation found 4A and 7F incorrect or bad.
This is a firsthand physical repair case. The same symptom on another Pac-Man or Ms. Pac-Man PCB can have a different electrical cause. Use the documented diagnostic observations and tests to guide troubleshooting rather than replacing a component solely because it repaired this board.