On an S+ machine, the color of the two wires on the door emitter optic should be black and red.
The color of the two wires on the door cabinet reciever optic should be white and red.
I've put these in backwards sometimes myself... just something to check.
Make certain that they are lined up as perfectly as possible.
Buzz has found an excellent way to get them lined up...he uses some masking tape on the cabinet and a magic marker.
While you're at it, check the Reset key switch and wiring.
A hand-held multimeter with the unit set onto "continuity" mode is great for checking wiring for breaks.
Mainly, it sounds like one of your door your optics are not working correctly.
or
Your ram chip is stuck in the dreaded [61-1] "Loop".
The [61-1] Loop is when you close the door and turn the Reset key and the numbers on the reel glass display go back to [61].
I'm not sure if that's the sequence of your display at the moment or not.
However, you've already performed a Clear and that should have gotten rid of a "stuck" data byte.
The Clear chip sets all the data bytes on the RAM and motherboard chip to zero's or one's...I forget which.
Doesn't matter tho, either way, the Clear procedure should have broken the "Loop".
Another thing you could try is a swap of the RAM chip from the other MPU board onto this MPU.
Your present RAM chip could be faulty.
If that doesn't work, then it's possible the motherboard chip is faulty.
Swap one thing at a time to rule out parts, you've got some work to do but
that's the fun of our hobby! - to figure out how to make it work!
Pictured below is lining up an S+ upright cabinet door optics using masking tape.
Pretty simple trick to get them optics looking at each other!
I'm not quite sure how you line a slant door optics tho?
I've never had a slant machine!...>>>
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