F-14 is the system 11 game that I most often have to replace transistors in the special solenoid section and the weird part about it is that the diverters are computer controlled and thus not prone to locking on from a stuck switch like the slings and pops.

After repairing 1 or the both of these diverter coils on literally over a dozen machines I finally noticed that the diverters are usually wired to the purple and yellow 50 Volt coil circuit.

Now what's odd about wiring them to the 50V circuit is that they do this without any intermediary device between the 50V at the coil and the TIP102 on the board. Originally at the time Williams would use a snubber relay board to activate 50V coils. They would use the TIP102 to drive the 24 Volt relay and that relay would connect the coil to the 50V circuit. Later they used little boards that had TIP36 transistors on them in place of the relays and finally put those transistors onto the AUX driver board. Later on WPC system they did drive 50V coils directly from TIP102's.

I had debated whether to switch that 50V source at the fuse holder under the playfield to 25V and this might prevent the coils from melting and blowing the TIP102 transitors. Then I ended up with a Sample F-14 and found that those coils on that game were wired to the 25V red/white source. Same mech, same value coils. The game works fine and the diverter arms did not appear to get pushed out of the way when the ball hits them, so I'm not sure why the change occurred at the factory and at which point during the run they did it.

This game is what made me seek out a fix to the achilles heel of the system 11 board set and I've seen 2 different approaches, individual coil fuses and a one shot input board.

So long story short I believe that changing the coil voltage on the diverters on F-14 from 50V to 25 should help prevent the game from burning up those transistors randomly.

Nice catch. I'll have to check again next time I'm in front of one. I think there's a switch on the shooter lane wireform about halfway up.

The diverters have a dedicated fuse (a single fuse they both share though which should be OK as I don't think they are even supposed to fire at the same time) . If you look in the upper right corner of the bottom of the playfield (lower right when the pf is tilted up), the purple/yellow wires connect to a fuse holder somewhere beyond the upper right flipper. This would be the ideal spot to jumper to the 25V coil power, on the feed side of the fuse as I believe only the 2 diverters are fed from this fuse.

You cannot just replace the power going to that fuse like I suggested earlier as the 50V also feeds the jagoff kicker after going to the diverters.

Just fixed this on a friend's game this weekend. She had put inline fuses on both coils (not sure of the fuse value) and it still managed to melt the coil and blow the transistor before blowing the fuse.

So just like others in this thread I simply removed and taped off the purple/yellow wires going to the two diverter coils (keeping the daisy chain intact) and ran a new wire from the pop bumper red/white wires to the 2 diverters. Worked like a charm.