Weirdo Coin-mech wiring help. - Resolved

[SuperDeadite]

So let me explain, my cab is wired for JAMMA, but often when booting up a game, a credit is automatically added. This is creating problems for my new Crack Down board which thinks Service is being held down, and goes into floppy back up mode everytime.

Beyond that, if I insert a 100yen coin, it adds a credit, and there is also a push button which adds a credit.
So I wanted to correct this and here's what I found.

Jamma Coin 1 -> I don't know, the wire disappears into the bundle and I can't tell where the fuck it's going, i think it might be spliced as the wire on the harness doesn't have a color match on the other end, or maybe it isn't connected to anything.

Jamma Service -> 500yen line on the coin-mech

Credit adding push button ->100yen line on the coin-mech

The credit lines are also connected to some resistors which go to an analog lifetime credit counter under the coin-box.

Now the credit adding button only goes to the 100yen line on the mech as far as i can see. So it appears when you push the button, the coin mech must then be triggering the 500yen line which goes to the service pin on the harness, as otherwise the board wouldn't be talking to that button.

So I can think of 2 options to try:
1. Change the wire going to JAMMA Service to JAMMA Coin 1. And add a new independant service button.

2. Just wire Jamma Coin 1 to the 100yen line/push button. And Service should go to a new button. While the 500yen line can simply be cut.

This sound about right? I can't find any info on a coin-mech that has multiple lines for different coins. If only I could figure out where the hell Jamma Coin 1 is currently going. XD

[Ed Oscuro]

Call me stupid, but...did you try running a multimeter with one lead on the known end of Jamma Coin 1, and testing all the others? If you can reach that far with a probe (maybe add a wire)? Interested as much for my own edification as anything else - not very familiar with using the multimeter really.

[SuperDeadite]

Solved.

I pulled apart the rats nest of wires and finally figured this out, there was a wire splice hidden deep in the middle. JAMMA Coin 1 actually goes to both Coin Mech 100yen out AND the add-a-credit button. So it seems to be wired properly. However, Coin Mech 500yen out is connected directly to JAMMA Service. All I had to do was cut that connection, then add a proper service button. Weird as hell way to wire a cab though. I suppose the idea was if you used a 500yen coin, it would then add 5 service credits since a customer wouldn't know the difference, still weird though.

[Ed Oscuro]

Oh, I guess that explains why the multimeter wouldn't solve it (should have realized that from the first post).

Is this analog credit counter a typical thing? Who makes it?

[SuperDeadite]

The credit counter looks like an old "flipping number clock" from the 80's if you know what I mean. My cab is an old 18'' wooden table that used to dominate Japan. I have no idea who made it or what it originally was meant for. When I got it was wired for JAMMA and a CPS-1 kick.

[Ed Oscuro]

Yeah, I do. Sounds pretty fascinating...in a scary way.