T-Rex Issues Resolved and Preventative Measures
So I read through the posts after my initial post regarding the problem with the T-Rex not starting events properly, namely would not release the ball during T-Rex Multiball. Since that time I opened a ticket with Stern and spent a LOT of time trouble shooting. I have taken that poor dino apart more time than I would care to admit, and I learned a lot about how it works. I thought I would pass along the biggest lessons in case anyone else is having similar issues or you want to do some preventative measures to keep this from happening.
Cause of the problem:
Jaw Optos not registering. You can check in switch test by sticking your finger in the T-Rex Mouth - if you don't see it register things will get more intimate between you and your Rex, FYI.
For me, this problem was caused by two things. And those, in my opinion were a result of fatigue caused by the movement of the T-Rex during play.
1. There was a broken solder point on the lower jaw opto positive that broke due to fatigue. Stern had sent me new optos to try and I actually missed this break during that swap. It wasn't until I went back through my photos I noticed it.
2.The ground wire for the top opto had a break in it. The wires for both optos are shrink tubed, run down the "neck," and are zip tied in place. Once I had replaced and repined that wire into the molex connector everything worked and the optos registered on the switch test.
1. For the ground wire I added a double layer of heat shrink to that whole bundle of wires running down the neck. I also did not zip tie then down as tightly as they can go to keep them from pinching the wires and breaking one of them again. Tight enough to keep them in place, just not torqued down.
2. I added two zip ties and shrink tube to the lower opto wires to help create a flex point in the wire itself and not on the solder points of the opto board. This will probably be controversial as one of them runs under the opto board itself, but I think this will be a huge improvement.
3. The two connectors for the optos that come up from under the playfield are shorter than the other wires - the ones that connect power to the motors). I added about 8 inches of wires for each of these to give a little more slack to the movement. This should prevent causing a fatigue malfunction under the playfield now that I have prevented them in the T-Rex itself - the fatigue malfunctions may have been a result of these being too short in the first place. This one requires more shrink tube, soldering, and repining all the wires to the connectors.
I hope this is helpful. I love this title and it was a bummer not having the T-Rex working. My wife and I just put a couple hours on it yesterday and everything seemed to be working great!