Arguably, Bally’s Addams Family is one of the greatest titles ever produced. According to IPDB.org 21,270 units were produced including 1000 Gold Special Editions. It had broken all sales records for flipper games up to that point. It’s definitely a highly coveted game.

Unfortunately, with all great games, they are usually heavily played and worn. One of the common problem areas on Addams Family is the center of the playfield where the three magnets are located. Transistor failures when they lock on will cause the magnet to overheat and eventually burn the playfield. They are meant to have a short duty cycle which just means they are intended to only be pulsed in short bursts. They aren’t designed to stay on for any length of time.

To protect the game and playfield, several aftermarket parts suppliers make a simple fuse kit that plugs inline with the magnet connectors. If your game doesn’t already have them, consider investing in them, ASAP

I get a call from a previous customer who tells me his Bally Addams Family pinball is randomly shutting down. I start a game and after a minute or two the game shuts down. Typically, William’s WPC games with random shutdown problems, will shut down when hitting the flippers, usually when hitting both at once. When this happens the first thing to check/replace are the two bridge rectifiers under the heat sink.

Another place to check is the power input connector J101 on the driver board, pins 1 and 2. Usually the two red wires will overheat causing weak connections which results in reduced current flow.

That wasn’t the case here so I put the game into coil test and after so many tests in, it would shut down, always at the same spot. The problem is I couldn’t see what test it was failing on, so I took my phone out and made a video of the display during the test and played it back to see where the failure point was. Unfortunately I didn’t save the video so I can’t show it to you here.

I was able to track the problem down to one of the playfield magnets. Whenever it was fired it would cause the game to freak out and reset. I unplugged each magnet but the game would still shut down on the magnet test. I unplugged the connectors on the magnet driver board under the playfield and the game stopped shutting down.

This isolated the problem to the magnet driver board. I pulled the board and measured each of the transistors and they all read fine. There’s only a few components on that board so that really leaves only one thing, the diodes. There’s one for each transistor and D2 was shorted.

The diodes are there to protect the transistor and the rest of the drive circuitry. In an upcoming post I’ll go into more detail as to why the coils all have diodes on them. You may have noticed that some games don’t have any diodes on the coils.

Thats because starting with System 11B games, the ones with the auxiliary power board below the power supply, through WPC-95 have the diodes on the driver board. I’ll go into more detail on that in the same upcoming post.

Fortunately nothing else was damaged. I replaced the diode and the game was back to normal.

I hope you learned something about figuring out the process of how and why things work, but more importantly, how to think through the troubleshooting process.

Until next time, Frank