MK button help.

ArcadeDad79

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OK. I have complained about this MK conversion cab all too much.
Aside from getting shocked when i touch the inside metal,.i have no LOW KICK only on Player 2.
The pcb has several failed roms,.and sound probs,.but aside from that,.all buttons normally worked.
I came across a new MK pcb. When i plugged it in to test it,.man...it was beautiful.
All sound and pic were great (removing the past idea my monitor was bad)..BUT, on THIS new pcb,.the pinout (header?? i dont know the terminology) has a few .100 grade pins broken off.
This is were the kick connector go's onto the pcb,right next to where the sound board plugs in..again,.i think its the "kick connector" but i dont know what its called.
So,.when i plugged in,.(even though the pins were gone in 2 spots) i had NO LOWER ANYTHING ON EITHER PLAYER.
No low kick or punch for EITHER.
SO,..naturally i put back the failed ROM pcb ,.mainly because i can at least play it. Maybe no sound and an ugly pic,.but playable.
HOWEVER,.now,.for WHATEVER reason,.my player 2 LOW KICK doesnt work.
I opened the CP,.i see no loose wires. The ground and other wire are intact. The button is clicking away....
Could the button just have gone bad??
What happened in swaps? i understand the new pcb not working,.because pins were broken off,.but the original always worked untill re-install.
SO,.if i pull that "kick connector" and keep moving it around,.i just get differnt results.
if i move it over 1 pin,.i lose another button,.but if i move it over 3 spots,.all buttons work,.but way off. if you hit P2 block,.P1 will punch,.and so on,.
So,.out of frustration,.nothing is in there.,
i have 2 pcb,.1 works awesome,.but has broken pins,.
1 is shit,.but plays,.minus P2 LOW KICK.
what the hell happened,.what do i do?
Send the good board to one of you?? to fix the pins that snapped?
who can test this board,.and fix what i need?
Help??
in So Cal (murrieta) *also,.i pulled out the drawer in the front that holds the pcb and Power Supply,.i found a dangling brown wire,.. looks like it was cut ,.what wire is this? important? is this wire why im getting shocked?
 
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I don't know if this is much help but i remember when I had my MK board I had the same trouble with the kick harness and buttons being off on both sides. I just moved it around until they all worked properly. As far as you getting shocked, it's hard to say if it's due to the brown wire. Where is that wire coming from again?
 
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I'd replace whatever roms are bad on the good player 3 harness board with the roms from the bad player 3 harness board.

the one that's got the broken off pins, you might be hooking the harness up a couple pins off.

as for the shock treatment, I don't know. I'd backtrack to the isolation transformer/AC input, see if any of your power wiring looks like it's been hacked up. by hacked wires, I mean do you have any wires in there that have been spliced that aren't the same colors on both sides or shit like that. :)

I've got 3 of the newer MK2/KI style Midway cabs that have NEVER shocked me before, I'm gonna have to say check that you don't have any AC wiring touching metal inside there. it'd probably be beyond the isolation transformer in that case if your monitor hasn't flaked out at all.

I'm no electrical wizard, just take a look for anything that's obviously messed up.

maybe take pics.
 
ok

hey mecha,.
the "good board" doesnt need any ROMS.
Everything on that board test perfect,.and it looks beautiful.
The prob with that board is the broken pins,.no matter what i do there,.the buttons dont work.
Now.,can i take the P3 header (the entire socket) out and put the one from the bad board on?
My concern is that it wont fix the problem,.
because even with the BAD PCB (failed roms) im missing player 2 LOW KICK,.and it isnt missing pins,.and it NEVER gave me a problem before.
So,.if i use the failed rom board,.which plays fine,.i have NO P2 LOW KICK,.should that be a button that needs replacing or is that prob still on the pcb somewhere?
I want to use the good pcb,.it passes everything,.but its pins are jacked up.
Also,.i cant remove ROMS from one to the other because these 2 boards look totaly different.
On the bad pcb,.i have a failed UC8,.but on the new good pcb,.there IS NO UC8 (that i can see) and EVERYTHING is different!
???
 
sounds like one of your boards is a Y-unit and the other is a T-unit. :)

you're correct, the roms aren't interchangeable.

the reason your low kick doesn't work on the T-unit board is more than likely because you have an MK1 cab with the kick harness that's for the older Y-unit.

in which case, I know it's MK1, but you need an MK2-MK4 kick harness for the T-unit board.

Mortal Kombat was originally produced on the older Y-unit hardware (like a majority of the Williams/Midway games that came out between 1990-1992) and the player 3 header (the correct terminology, as you so eloquently inquired earlier. :)) has an entirely different pinout from the T-unit style. later in MK1's production cycle, Midway moved it to the then-newer T-unit boardset, which was home to NBA Jam, Jam TE, MK2 and I think the Judge Dredd prototype, and likewise it inherited the player 3 pinout that was on NBA Jam or MK2.

hope this helps. if you're handy with a soldering iron you could replace the broken off pins with relative ease, but I still think it's a kick harness incompatibility that's causing your missing low kick problem.

I don't know the pinouts off hand, which could be found in the game manuals located under this category here: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/

or alternatively, you can shop for the MK1 or MK2-MK4 harnesses at http://www.jammaboards.com/, that's where I bought mine.

OR alternatively, if you can you can rearrange the wires in the snap-top header on your existing kick harness, you can figure out the correct pin offset (the MK1 one is like a 10 pin header, I think MK2s might be 12, I forget, haven't messed with my MKs in a year and I work on dozens of games every year lol) and save money and just make it work that way.

if you're unsure of which of your boards is Y-unit or T-unit, there's pictures here to compare with:

http://www.vm68.com/mkromhacks/mk_t-unit.html

the T-unit one I think also says "MORTAL KOMBAT REVISION x.0 T-UNIT" after the rom check finishes.

did you look into your shock treatment problem at all? maybe hooking the wrong harness has electricity outputting out of the wrong pins LOL
 
man,.great info,.very confusing.lol.
My trip is,.the older MK that i was using,.never had any problem with any buttons.
NEVER.
Everything worked. (10 pins) everything was good.
I put in the t-version,.(12+ pins) and had probs,.which now i undersatand is about the harness,..BUT
when i put the old (failed ROM ) board back,.shouldnt it STILL play fine?
why would only 1 button,.only only 1 player,.not work now?
Regardless,.the problem is that i want to use the t-version,.as it works perfectly.
SO,.my options using THAT board are a new kick harness,.or replace the pins/header?
Can i take the 10 pin header off the old model,.and put that on the t-version (12+ pins)?
or will P2 LOW kick still not work?
If i get the MK2-4 harness,.is that an easy swap?
I see where the kick harness plugs into the pcb,.but what of everything else?
Do i remove EVERY wire from EVERY button,.and just put this new harness on those buttons.?
Is it a bunch of scary wiring,.or are the wires labeled for noobs?>
im afraid if i buy a newer harness,.i wont be able to put it on right...
i dont get this!
 
wow.
thnx to your diagrams,.i figured something out.
THE OLD FAILED ROM PCB I ORIGINALLY HAD (working perfectly fine,.just failed ROM) IS THE T-VERSION!!!

The NEW pcb im trying to use is the older version,.with the 12+ pins.

My T-Version has the 10 pin header...and a failed UC8 as well as others.
My old version FAILS NOTHING,.but has broken pins,.
now what?
 
get a desoldering iron from Radio Shack, suck the solder off your donor pins, and remove the broken off ones from the board you want to use... install the donor pins, solder, and be merry. :)

I'm at work now and on the run, I'll probably not be able to respond for a couple hours.
 
thank you mecha.
that is a very helpful answer.
I can wait for a reply.
So,.i can take the pins from the NON t-version and pop them into the t-version?
same diameter pins and everything?
Do i need to replace the entire header,.or can each pin individually come out?
thankyou man.,your a help!
 
pins can come out individually. that rubbery plastic part can be pried off with some finesse and a little precision flathead, then maybe a 1/4" head for the rest of it. or you can cut that plastic part with maybe a xacto knife for your donor pins. won't look as pretty, but at this point I'd say functionality comes first. :)

are you sure that those pins are even used btw? there's a lot of "empty" pins, cause the Player 3 header is for joystick and button/start/credit inputs, and this is only for 4 inputs vs. like 10 lol

I'd read the manual over, make note of which pin is Pin 1 (they're labeled) .. there's separate manuals for the Y-unit and T-unit boards on arcarc.xmission.com.
 
The fun part with the manuals is that there's a typo with either the t-unit manual or the t-unit addendum/bulletin. I'll look for it in the morning, I think it's to do with the kick harnesses.
 
this is so frustrating.
I tried plugging that thing in every which way.
It used to work,.like yesterday!
When you say the rubber plastic part,.are you talking about the header?
I thought that thing was soldered on?
Am i to go and try to pry the header off?
I know some pins may not be used,.but i dont know which,.im so confused.,
i want to buy ANOTHER board and be done with it,.but i have a feeling that wont help
 
Bad dudes

LOL.
My MK is now BD.
The bad dudes looks and sounds great,.the game is actually a nice change from fighting the same old characters,,,...
i think i will convert my MK into a generic whatever cab,.that plays anything,
its a cool cabinet,.because the pcb is in a drawer in front,.so swapping in new boards is so easy.
Since it isnt original/dedicated,.and there is NO artwork (but does have a beat ass MK CP,.and nice MK marquee) i figure its a good cab to just play anything in.
It has 5 buttons,.so it can play ALMOST any games,.
MK gets repeatative,.so now its BD.
Thnx guys for your help,.but for a noob like me,.it may be easiest this way,.for now.
 
The fun part with the manuals is that there's a typo with either the t-unit manual or the t-unit addendum/bulletin. I'll look for it in the morning, I think it's to do with the kick harnesses.

hilarious. :D

well, we're talking about how to resolve this.
 
LOL.
My MK is now BD.
The bad dudes looks and sounds great,.the game is actually a nice change from fighting the same old characters,,,...
i think i will convert my MK into a generic whatever cab,.that plays anything,
its a cool cabinet,.because the pcb is in a drawer in front,.so swapping in new boards is so easy.
Since it isnt original/dedicated,.and there is NO artwork (but does have a beat ass MK CP,.and nice MK marquee) i figure its a good cab to just play anything in.
It has 5 buttons,.so it can play ALMOST any games,.
MK gets repeatative,.so now its BD.
Thnx guys for your help,.but for a noob like me,.it may be easiest this way,.for now.

MAME the fucker add a sixth button for games like SF and enjoy getting more use of out of it than just one game ;)

Good luck :)
 
Okay, it's hard to decypher but it sounds like the kick harness you have is 10 pins? The Y-Unit kick harness is 12, the T-unit kick harness is 15 and they connect to different headers. Street Fighter has a 10 pin kick harness. Here's the pinouts:

Y-Unit (connect J4) :
1 - GND
2 - N/C
3 - N/C
4 - P1 Low Punch
5 - GND
6 - Key
7 - P1 Low Kick
8 - N/C
9 - P2 Low Punch
10 - P2 Low Kick
11 - N/C
12 - N/C

T-Unit (connect P5 (not keyed)):
1 - GND
2 - N/C
3 - N/C
4 - N/C
5 - N/C
6 - N/C
7 - P1 Low Punch
8 - P1 Low Kick
9 - N/C
10 - N/C
11 - P2 Low Punch
12 - P2 Low Kick
13 - N/C
14 - N/C
15 - N/C

I'm pretty sure it was the sound board connection one that was typo'd in the service bulletin, to do with sound not kick harness on a second look at it. If the one with broken connectors has those at a N/C or "key" pin, then you don't need to bother trying to do surgery on those pins.

So are you using a 10 pin kick harness? Or trying to plug a kick harness into a 10 pin header?
 
10 pin header is one board
15 pin header is another board
(15 pin header has 2 broken pins)
10 pin header always worked and played fine,.but now has no low kick on player 2
the 15 pin header is the one i want to play.
 
you know the overall shape of the switch holder part of the buttons? the one part that has the tail like plastic piece facing furthest downward is what holds a corner of the microswitch, use your fingernail to pull outward on that while sliding the microswitch downward. then unhook the kitty-corner of the switch and the whole thing will come out.

from here you will be able to unscrew your buttons out.

about microswitches, since I'm sure you don't know about these yet...

there are 3 terminals on them, assuming the very bottom L-shaped one is in fact on the bottom, it goes in order (top to bottom) NC (Normally Closed), NO (Normally Open) and COM[mon] (Ground)

the wires going from your JAMMA harness will go to the 4 switches that make up the 4 directions (8 if the joystick actuator is pressing 2 corner ones at the same time of course), the switch for your start button, and in the case of MK, the switches for the high attacks and block. the JAMMA standard only allots for the switches I just mentioned, hence why the "kick harness" is needed, and technically for MK it's really the "low attack harness", but that was the name that was assigned back in the Street Fighter era and it's what's stuck. :)

there is really only 1 ground wire for all of these, obviously, it's just branched off into a bunch of different points to go to each button (or other points, like your video signal cable, but that's a whole other subject). the way the microswitch works is that under normal operation, your input wiring will go to the NO terminal, and whenever your press down the button or activate a direction on the joystick, the circuit is then "closed", or completed, and it registers on the game that you're moving left or you did a high punch, etc.

on games where I've redone ground wires, I daisy chain each wire from one switch to the next (literally going from P1/P2 ground to the up, right, down, left, start, JAMMA 1, JAMMA 2, JAMMA 3, kick 3, kick 2, kick 1 in the case of my MVC2), which effectively means that if you cut the ground running between the start and the quick punch on my MVC2, you won't have any attack buttons that work, cause they're no longer grounded.

I tell you this because in my Killer Instinct cab (same build as your MK, at the heart of it all) I had frayed wire ends inside the quick disconnect terminals or outright broken wires and I re-crimped new ends on the ones that didn't work right. after switching many games in and out of that machine as well, I wiggled some JAMMA pins loose inside the JAMMA connector and would lose button inputs on Player 2 until of course I wiggled them back to where they made connection again, and left the machine as a dedicated KI, not a swap machine. :)

be that as it may, what I'm telling you is try switching your suspect Low Kick input wire to another switch that you know works (say Low Punch), and likewise take the one that works and switch that to the one that was used for your Low Kick. you have only traded the wires between the two switches now.

1) if you have a working Low Punch and a non-working Low Kick, your problem is in the wiring.

2) if your Low Kick works, but not Low Punch after the swap, then your switch on the LK button is bad and needs to be replaced ... OR ...

you have a potentially bad ground wire, so then you take the next step and swap the ground wires between the switches.

3) if then the "Low Kick" (wired to the switch in LP that is) stops working again, and your "Low Punch" (wired to the LK button) works (whereas it didn't in Step 2 before) then your ground wire is bad. fear not, that's an easy fix if you have the tools for cutting/stripping wires and a pair of crimpers for putting a new quick disconnect terminal on OR a soldering iron to jump the good ground to the one that had a bad ground.

as you can see, there are dozens of possibilities here. just dig in and don't be afraid of what happens... you'll learn new things every time you do this.

did you ever find out the shock treatment cause yet?
 
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