Monaco GP Cockpit won't coin up...

vintagegamer

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Taken from my post in the General section....


The main issue with it is, the little mobob lever that the quarter hits to recognize a credit broke off (prior owner issue, not me!), and the 3 wires (white, black, and orange) that normally connect to it are hanging loose. I checked all 3 with my DMM briefly and they appear to be registering between .01 and .03 volts. I need to find out how to bypass them to see if the game will coin up. Something is telling me the temporary fix will require a paper clip and a schematic, but I am putting the issue out here for the "experts" to chime in as well. The guy said the game played fine up until the coin lever piece came off so, I'm hoping it will be an easy fix! It also doesn't look like the game has a free play option so, so much for that idea.

I checked the fuses that I spotted in the back with my DMM and they are all good.
 
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iirc,

white = signal input (should be measured 5v)
black = ground
orange = +12V

Thanks mrdion,

I looked at the schematic but for an untrained eye like mine, it's just looking like a bowl of spaghetti.. Plus there are details about the coin setup on there that look like they are pencilled in..

I think I also had a poor ground last night when I was doing my check so hopefully I can check it again tonight.

I'm just hoping that there isn't damage to the board since that switch piece broke off.
 
OK, here's the latest. I got to retest the 3 loose-hanging wires, and they are as follows:

orange: 4.9V
black: 4.9V
white: 0

(these wires, according to the owner's manual, originally went to some accelerator board or something)

With Oryk Zinyo's help, I have located a part which I think is the main part of the mystery. I've attached a pic. It has 6 tabs running up the left side, and as you can see in the pic, tabs 1 and 2 had wires on them which appear to have broken off. Tab 3 is a ground wire (white, and I used this one to test the other 3 mentioned above). Tab 4 is a blue wire which had a very minimal voltage reading, and then the remaining 2 wires (red and yellow) were registering 4.9V each.

Since the guy mentioned there was a coin switch in the setup that had broken away, is it safe to assume that one of the 4.9V wires in the top trio (orange, black, white) would need to be touched or connected to one of the tabs on the part in the pic at slot 1 or 2 to make this game register a credit?

PS: the crap on that board is disgusting!!!!!!!!!!
 

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Another update: the "tab 1" on the part in the picture is showing on the wire diagram as the "normally open" tab. Tab 2 is showing as the "normally closed" tab. Would applying one of the 5V hot wires from the white-orange-black trio to tab one "close" the circuit and in turn, make it credit up?
 
I believe that tab 1 should be connected to the normally open tab on a switch with tab 2 to the normally closed. Conect tab 3 to the ground of the switch.

It is possible that you can get the machine to coin up by alternating a wire that has one end continuously connected to tab three and the other end starts on tab two, moves temporarily to tab 1 (breaking the connection to tab 2) and then back to tab 2. At the very least this should cause the screen to flicker and add a coin to the coin counter, assuming one is attached.
 
I believe that tab 1 should be connected to the normally open tab on a switch with tab 2 to the normally closed. Conect tab 3 to the ground of the switch.

It is possible that you can get the machine to coin up by alternating a wire that has one end continuously connected to tab three and the other end starts on tab two, moves temporarily to tab 1 (breaking the connection to tab 2) and then back to tab 2. At the very least this should cause the screen to flicker and add a coin to the coin counter, assuming one is attached.

Thanks Oryk, I will give it a try and report back.
 
I tried the wire-hop option (Oryk's second suggestion), and I can hear a little static in the speakers during the hop but nothing else happens.

I won't have time today to solder up the switch because we have to go out tonight, so I'll have to see if I can try tomorrow.

In the meantime, is it possible for one to buy a replacement Sega "credit unit" board? That's the one that's shown in the pic I listed earlier. I wondered if maybe this board is just hosed and could stand to be replaced?
 
Here's today's update...

1. I tested the coin switch that came with the game using my DMM, and when putting the red and black wires from the DMM on the NC and NO connectors, I heard no beep until pushing down the lever on the switch. So, the switch is OK.

2. I ran wires from the coin switch to tabs 1 and 2 on the credit unit part 95539, in the order that Oryk provided. I held the ground wire from the coin switch on the number 3 tab of the credit unit board, and upon flipping the lever on the coin switch nothing happened.

3. I took the DMM and put the black lead on the ground tab of the credit unit, and put the red lead on the NC and NO wires on the coin switch to make sure my amateur soldering skills weren't the crux of the problem, and both wires read that 4.9V were getting to the coin switch. The only thing that was throwing me was, when I touched the red lead on the common tab of the coin switch, it too read 4.9V. I thought that should read zero but I was just happy at that point that voltages were getting to the coin switch from the credit unit board part.

I'm bummed because this is telling me that the credit unit board must have a problem on it somewhere. It looks like a cat vomited on it so God only knows which component is the issue. The other bummer is that I haven't seen any of these credit units up for sale, but I've only just started looking today. I'd love to find out about a universal credit unit that I could wire in and call it a day, or some other kind of work-around to remove this part from the equation. Nevertheless, that's my latest update. Still taking suggestions!
 
never heard sega using some kind of credit board.

there should be wiring diagram in the manual. you can trace those cables with it.
 
PROGRESS!!!! Although I'm not there yet on firing up a game, I'm so close it's crazy!!!

After looking at MacPDaddy's pics again, I noticed that the red and blue wires running to the coin mech in his game looked familiar with some in mine. They definitely didn't look like the wires the seller had said he used to power up the game.. The ones in MacPDaddy's machine were a thicker gauge (around 10ga). I looked around in the coin area on the cockpit and lo and behold, were the red and blue wires, same gauge, running to a HOMEMADE switch that was mounted in a hole that looked like it had been done from the factory. I didn't even recognize it up until now.

I hit that button a few times and could see some flickering in the screen, but no credit up. I cut the red and blue wires from that switch and put them on the known-working one I tested yesterday to make sure it was good. All I needed was a ground.......... I found a wire inside the coin area that looked like it was to be an earth ground, hooked it up to the common tab on the switch and nothing happened credit-wise upon flipping the switch. I then went to a wire that I "thought" was a ground wire, and hooked an alligator clip to it and then to the common tab on the switch, hit the switch and....................

EVERYTHING WENT DEAD.................... :(

I looked around in the back and found that I'd blown one of the 4A fast blow fuses on the power brick. The closest I had in the tool bench was a 5A fast blow so, I disconnected my switch, and started the machine up to make sure it was OK. Everything came back up thank God!!

My question at this point is, what is the best ground I can use to test this again? And, just being proactive, if I had the NC and NO wires reversed, would something like this happen upon actuating the switch (my guess is NO because you're basically closing the circuit to allow voltage pass as I understand it, but I'm just confirming).

I'm thinking if you guys can help me to determine what is the best ground to hook the switch to, I might be playing this game by the end of the week! C'mon guys!!!!
 
it looks like you're shorting 5V and gnd directly, then it blows the power supply's fuse.

just to be save, you can use that gnd, but with a resistor in series, you can use 330 ohm or 470 ohm.
 
A person over at BYOAC said to use the red on the NO tab of the switch, and the blue on the ground tab of the switch and that should work. It didn't.

Is there anyone who can help me to locate a suitable ground to use on this game without having to add a resistor into the series? I'm guessing I'd have to go to Radio Shack for one of those, but have never done any resistor-oriented work before.

Because this game has multiple boards in it, I'm concerned about picking the wrong ground and damaging something. In my current experiments, the colors on the screen already look a little different so now I'm scared I might have done something to the monitor chassis. :(

I can't believe this can be so complex.
 
Maybe this will help??

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Thanks so much for the pic Scott- well wow, this mystery just keeps getting stranger! Your credit unit card there has yet another different configuration than mine has. However, I see one point in common: if you look just below the white wire that's soldered on the board, you'll see the red and blue wires that I'm currently thinking are the NC and and NO wires. Like mine, yours are taped together, separate from the rest of the pack. Is your game a cockpit version? And also, can you see where those red and blue wires run to?

I'm starting to see why the previous owner bailed on fixing the coin switch issue LOL
 
I'll try to dig around tonight. There are 2 sets of red and blue wires. The heavy guage set has nothing to do with the coin up. It is the monitor degaussing circuit.

I here is the coin switch..

attachment.php
 
I'll try to dig around tonight. There are 2 sets of red and blue wires. The heavy guage set has nothing to do with the coin up. It is the monitor degaussing circuit.


Well then that explains why the screen 'bounced' and the colors now look a little funky.. Hopefully they go back to normal on their own! :(
 
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I'll try to dig around tonight. There are 2 sets of red and blue wires. The heavy guage set has nothing to do with the coin up. It is the monitor degaussing circuit.

I here is the coin switch..

attachment.php

I'm going to look ASAP to see if I have those smaller gauge wires. Thank you!
 
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