Hi, I’m Frank and I’m a dumb f**k. Yes I’ve spent more time than I’m willing to admit chasing a “problem” that wasn’t really there.

When you put LEDs in some games, you can get “ghosting” even when using non-ghosting LEDs. Ghosting means the LED lights dimly when it’s not supposed to light at all. This is an artifact of the way the lamp matrix is driven. LEDs require far less power to turn on than incandescent bulbs and this can cause them to light dimly.

So I was on service call for a William’s Red and Ted’s Road Show. The problem was the check fuses 114 and 115 message was coming on the display which will keep the game from running. The customer stated fuse 114 was blown, he kept changing it until he had a burning smell at which point he stopped f**king with it. (Why do people do this?)

I didn’t suspect the bridge rectifier since I had replaced it during a previous service call, but still I checked it anyway since it’s the first thing I check when a fuse blows immediately. The problem ended up being a blown TIP107, Q91, which is the column 8 drive of the lamp matrix.

After thoroughly checking all lamps on column 8 and not finding any obvious problems, I replaced the TIP107 and hoped for the best. Turned the game on and everything worked fine. Maybe the transistor just failed for some inexplicable reason or customer was messing with something and shorted the column out, which no one will ever admit to.

One thing I noticed was the “Buy In” button, as it’s called in the manual, was flashing very dimly, which happens to be in column 8, row 7. All the other lamps on column 8 were good so I didn’t expect anything on the board.

So after XX amount of time checking the socket, the led, the wiring and the diode and almost pulling the board I realized it was ghosting and it doesn’t light in attract mode 🤦‍♂️. Putting the game in lamp test confirmed my suspicions and the LED lights just fine.

Before letting things get out of control, stop and go back to the basics. I forgot that on that day.

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