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Pac-Man and Ghosts Stuck in Upper-Left Corner
Repair Case Summary
This page documents a firsthand Pac-Man and Ghosts Stuck in Upper-Left Corner repair case.
It is intended for technicians and collectors troubleshooting original Pac-Man or Ms. Pac-Man arcade PCB hardware.
Date: 2017-06-07
Board: Original Pac-Man PCB
Category: Sprite positioning
Symptoms:
Pac-Man and all ghosts appeared in the upper-left corner.
The problem occurred during attract mode and during play.
Diagnostic observations / tests:
The 7489 devices at 2F and 2H were checked first.
Piggybacking 2H with a known-good chip made no difference.
Piggybacking 2F caused the screen to attempt to correct itself.
Components / locations investigated: 2F, 2H, 7489
Root cause: Bad 7489 at 2F.
Repair: Removed the old 7489 at 2F, installed a socket, and installed a replacement chip.
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.