Transistor Q54 on the CPU board fails, upsetting the switch matrix.
Monday Night Football: switch column transistor Q54 keeps failing
Cause: A lug on the outhole kicker coil (under the lower metal ball arch) touches the coil stop, putting 32 V onto the switch matrix.
Checks
- Remove the lower ball arch and look at the outhole kicker's coil stop and lugs for contact marks.
Fix
- Replace Q54 if failed.
- Insulate between the coil lugs and coil stop with electrical tape.
Systems
Games
Related tips
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Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Two, Clay Harrell (pinrepair.com)