The left flipper on our recently purchased Flinstones has started showing problems. The entire assembly and coil looks to be brand new. The EOS switch tests fine. I'm new to pins and this is my first real issue with one of our six machines. The assembly moves freely with no binding. From a cold power up the flipper works fine for about 5 minutes then power diminishes rapidly and the flipper heats up. The flipper isn't really very hot to the touch but compared to the properly working right flipper it is noticeably warmer.

This will be my first foray into pin diagnosis.

Powered on with the flippers at rest the voltage on the three terminals are 66.8V (for both right and left flippers)

Energized Right Flipper
Red/Green 45.7V
Yellow/Green 44.9V
Orange/Green 0V

Energized Right Flipper (hums)
Red/Blue rapid fluctuation
Yellow/Blue rapid fluctuation
Red/Blue rapid fluctuation

What is my first trouble shooting step?
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The opto board shows discoloration under the 26ohm resistors (blue) and delamination of the green solder mask over some of the board traces. I didn't check the temperature on the opto board until the machine had been off for quite some time and it was still quite warm to the touch.

I don't want to take a shotgun approach, toss in a new opto and damage it too. Is there something I should be looking at further up the chain that damaged the opto or do I just have a bad board.

Being new to all this, am I assuming correctly that the left flipper opto is erratic/freaking out and rapidly cycling power to the flipper causing it to heat up (and the opto board). Should I be looking at the opto sensor on the left flipper button itself as well?

Replaced with he opto board and seems like o be working. Will update was he thread if it acts up again

I was wrong my brother put the old opto board back in with the same issues.

Was that all flippers or just a single flipper?

I believe that I found the source of my problem. The previous owner did the building and dino lighting mods with each strand in a stackable jumper landed on J118 which is the Opto boards 12v supply. The Opto connector was in the back of the stackable jumper leading to the occasional check fuse message on power on and irregular 12v supply to the Opto board.

Will find out if that is the problem with enough gameplay

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