TZ Flipper issues

[Chris Bardon]

So last week, I ran into a problem with my TZ, which has been rock solid in the 10 years or so I've owned it. After I had people over for league, the lower right flipper stopped working completely. No obviously busted wires, coil wouldn't fire in test. Fuses are fine, opto boards are fine, and swapping them l/r didn't change anything. It looked like voltage was low at the coil and coming out of the fliptronics board, so thought that was the problem. I swapped the board with the one in my white water, and it worked, and the TZ board worked in white water. Wrote it off to either a cold solder joint that fixed itself by moving, or one of the cable replugs.

I checked it again tonight though, and this time the lower LEFT flipper stopped working (upper left was OK). For those keeping score, this is with the board that should be OK. I need to look at it again this weekend when I have some time, but wanted to see if anyone had any other suggestions. So far here's what's on my list:
-Check the fuses again. You never know...
-Validate the pinout going into the fliptronics board, and make sure power going in there is good.
-Double check voltage output from the fliptronics connectors
-Trace the wiring from the fliptronics board to the flippers and see if anything looks bad. Could be a short part way through? Seems strange that the problem would move though.

Given that the problem came back (sort of) when swapping the boards, I don't think it's an issue with that board. Maybe I'll try swapping them back and see if that changes anything? I'm kind of wondering if it's a bad connector between the board and the flippers?

Any other ideas?

 

[Locutus]

Just for clarification: you switched the flipper opto boards (l/r). Did you switch them back? The problem migrated from right to left. If you didn’t switch back, it could still be there?

 

[Chris Bardon]

Just for clarification: you switched the flipper opto boards (l/r). Did you switch them back? The problem migrated from right to left. If you didn’t switch back, it could still be there?

No, I haven't moved those again. The thought had crossed my mind, but when I originally moved the opto boards, the problem didn't move, so I thought they were good, but then again, maybe not? Might be interesting to see if it moves this time? Actually, what I might try is moving the boards between games and seeing what happens.

Then again, if it was the opto board, then the coil voltage would be 50v, correct? Low coil voltage would mean that the opto board should be fine as far as I can tell.

 

[Locutus]

Unfortunately I'm not smart enough to know about all of the voltages etc. lol. Just trying to apply another potential idea so you don't go chasing too far through boards/ wiring etc
When these flipper boards start to go, they will get flaky and work intermittently. I had to replace one side when the flippers would stop working one in like 5-10 games. Maybe swap back again, play some games and see what happens.
also, I've had some issues before on my TZ where reseating all of the connectors and ribbon cables numerous times solved the problem. Not sure if you've gone back and done this...
Have you tested all of the test points on the power driver board?

 

[Chris Bardon]

I've had some issues before on my TZ where reseating all of the connectors and ribbon cables numerous times solved the problem. Not sure if you've gone back and done this...

Not yet, but that's on the list as well. If one of those is flaky, cheaper than a new board. I'll get into it on the weekend, but glad I still have another WPC to swap parts with and test.

 

[Chris Bardon]

So I fixed it. Voltage was low at the coil, so I was tracing back up and decided to check all the fuses, instead of just the one that might be blown. This time, F901 was blown, which is the upper left flipper fuse, and that flipper was working just fine. F903 (lower left) was fine, but the lower left flipper wasn't working. This leads me to believe that the game might be wired wrong, since if I look at the circuit diargam, there's two gray/yellow wires coming off J907 to the left flippers. Given that both are 50v, it's entirely possible that these could have been wired backwards at some point and the game would still work the same, right? I can't think of another reason that an unrelated fuse could have anything to do with an issue like this. Left it in coil test for 5 mins or so, then played a couple of games, and fuse didn't blow again, so whatever caused it doesn't seem to be repeating. This is the first time I've run into something like this-it doesn't appear that this connector has been rebuilt, but then again, I'm not the original owner of the game, so it's entirely possible I suppose.