Jamma wiring issue. Start button for players 1 & 2 don't work

cmjb13

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Jamma wiring issue. Start button for players 1 & 2 don't work

So I was redoing some wiring in my Wrestlefest Jamma cab (converted to Sunset Riders), specifically relocating the start buttons underneath the control panel so I wouldn't have to ruin the CPO. Apparently, I got some wires mixed up as players 3 and 4 start buttons work fine. However, both Players 1 & 2 do not. I traced the wires from the Jamma connector and they are connected correctly.

Solder side 17> Start switch 1 (see start1.jpg)
Solder side U > Start Switch 2 (see start2.jpg)

There is no direct wiring between player 1 & player 2 which is what I suspect is the issue.
I'm going nuts here, but I traced what I could and cannot come to a reasonable conclusion on what I'm missing. I'm a newbie when it comes to wiring, so forgive me for any common sense things I may be missing.

Any thoughts are greatly appreciated.

Thank you.
 

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in the first pic, to the right of the yellow button is a cut black wire. is this black wire possibly the common ground your 1&2 player buttons share?
 
So I was redoing some wiring in my Wrestlefest Jamma cab (converted to Sunset Riders), specifically relocating the start buttons underneath the control panel so I wouldn't have to ruin the CPO. Apparently, I got some wires mixed up as players 3 and 4 start buttons work fine. However, both Players 1 & 2 do not. I traced the wires from the Jamma connector and they are connected correctly.

Solder side 17> Start switch 1 (see start1.jpg)
Solder side U > Start Switch 2 (see start2.jpg)

There is no direct wiring between player 1 & player 2 which is what I suspect is the issue.
I'm going nuts here, but I traced what I could and cannot come to a reasonable conclusion on what I'm missing. I'm a newbie when it comes to wiring, so forgive me for any common sense things I may be missing.

Any thoughts are greatly appreciated.

Thank you.

Did you confirm grounds are connected in the daisy chain correctly? Dod you use multimeter to verify connection?
 
in the first pic, to the right of the yellow button is a cut black wire. is this black wire possibly the common ground your 1&2 player buttons share?
I see that cut wire, but do not see the corresponding end.

Which Jamma ground pins should I be concerned about?
1,2,7, or 28?
 
I see that cut wire, but do not see the corresponding end.

Which Jamma ground pins should I be concerned about?
1,2,7, or 28?

Doesn't matter. You need to know that the ground attached to your button has continuity to any of those pins. Use your multimeter it's the only way to be sure.
 
pin 1,2,27,28 are ground on both sides of the connector. do you own a multi meter? if so set to continuity and check from your ground on the 1&2 start ( i think its grey in your pics) then test that cut wire to those pins to see if that is your ground.
 
pin 1,2,27,28 are ground on both sides of the connector. do you own a multi meter? if so set to continuity and check from your ground on the 1&2 start ( i think its grey in your pics) then test that cut wire to those pins to see if that is your ground.
I traced one of the grounds to the 2nd player molex connector. The wire on the corresponding molex end is missing. I suspect that's why a previous owner somehow hacked these wires.
 
I temporarily made it worse by having none of the player 2 buttons work. I was able to daisy chain ground from the working player 1 buttons. So now all buttons work except Coin 1 & Coin 2.

The Coin 1 Jamma pin is correctly connected to the player 1 coin microswitch. If I take a working ground from player 1 and connect it nothing... The coin 2 jamma pin appears to go to the coin door. That makes sense since I seem to recall the coin 1 button daisy chained to the coin 2 button (I'm kicking myself for not labelling prior to starting)

As a workaround, I can coin up from the coindoor, so it's not the end of the world. I'll keep trying....
I don't have a multimeter and really don't want to spend the money at this point.

Thanks for all your help
 
I don't have a multimeter and really don't want to spend the money at this point.

Thanks for all your help

Honestly not trying to be rude - but if you have arcade games and can't or won't spend $20 for a decent multimeter - you should get out of the hobby. It's very difficult to accomplish much without one (effectively). You will run into issue after issue where you need to check power and voltages and continuity...
 
So, after a good nights sleep, I took a closer look...

I traced the wire from the jamma coin 1 to the coin door. I split the wire off onto the player 1 coin 1 microswitch and did the same for player 2. Works like a charm....
 
Honestly not trying to be rude - but if you have arcade games and can't or won't spend $20 for a decent multimeter - you should get out of the hobby. It's very difficult to accomplish much without one (effectively). You will run into issue after issue where you need to check power and voltages and continuity...
Understood. It's not that I won't spend the money, just really never had the use for one.

Been in the hobby since my first arcade machine in 1993. Wow, 24 years....
 
Understood. It's not that I won't spend the money, just really never had the use for one.

Been in the hobby since my first arcade machine in 1993. Wow, 24 years....

Wow! My hats off to you if you have been in the hobby that long without a multimeter. I can't fix up one game without checking a voltage so I don't know how you do it... but somehow you are managing.
 
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