I fixed my TREX!
If your TREX is broken, I recommend the following troubleshooting steps.
1. If your TREX does not move body at all, but snaps his teeth, try physically tuning the body of the TREX until centered. There is a small switch that will be hit when it is centered. The TREX will not move up and down unless the switch is depressed.
2. To determine if your motors work, try applying 9v battery power to them directly for about 2 seconds. If it moves, it works. If it doesn't move, it's the motor. You will also notice that both motors have removable plugs about 2 feet down their wires. You can try switching the wire plugs and restarting the sequence. If the motor moves on startup, you know the motor is fine. Once you have confirmed the motors work, continue.
3. If the TREX does not open his mouth or move side to side, but moves up and down, your problem is on Board A. Try physically examining the board and the connections between them.
4. If your TREX moves side to side and snaps his teeth but not up and down, the problem is board B.
5. If your motors work, the TREX moves up and down and snaps his teeth, but does not move side to side, your problem is board C... the shaker motor power board. This was my problem. You can see that when I removed the board from my machine there was a big blowout on the back of it. I hacked the board and it now works like a champ. You can also get a replacement from MARCOs for about 90$. In any case, everything works on my machine 99% now. The last thing is fine tuning the right flipper switch (I'll probably just replace it at this point in time) and putting in some new twinkle bulbs for the bottom row of the backbox.
Hope this helps somebody and I'd be happy to help if anyone runs into a similar issue.
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