Thanks for the replies! I was getting afraid I would have to go this repair on my own!
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These machines aren't necessarily very complex but there are lots of wires and I'd hate to start messing with something that wasn't broke in the first place!
A copy of the schematics would be great! I had a spare coinco coin mechanism that I swapped in but got the same results. I also tried unsuccessfully to rig my machine for free vend. Based on these results I cleared my existing coin mechanism as the culprit. Is there something else I should try / check?
Thanks again for taking the time to help!
York!