IGT S+ Double Diamond Coin In No Credit Issue

[ikelly208]

I am a slot machine noobie and I have an IGT $0.25 S+ Double Diamond  slant top that is not registering coins/credits when coins are inserted.  I’ve read through every IGT S+ troubleshooting blog entry I could find on NewLifeGames.com and I’m not sure what to do next.   Any help you could provide on what to do next would be greatly appreciated.
Here is a quick rundown of what I have the issues I’m seeing and the troubleshooting I’ve tried:

Machine:  IGT $0.25 S+ Double Diamond  slant top

Issue: Machine worked flawlessly for several months after purchase. Now, coins go in and drop into the internal hopper (not the external tray).  No Credit for the coin drop is registered. 
When machine is powered up any coin in drops into the external tray.  Once the reels spin and the insert coin light, lights up any coins in drop into the internal hopper and do not register any credits. At this time the light tower bottom light flashes rapidly. No error codes are displayed.
Here is a video of the scenario I outlined above: https://youtube.com/shorts/6sqcWz6lUrU?si=B3auUsghz5xxhe0B

Troubleshooting I’ve done:
1.   When opening the slot machine I noticed that the coin comparator led was no longer lit green.  I verified that a sample coin was in place in the comparator.   I sent my coin comparator off to K*Lar Amusement Repair  for their coin comparator repair service.  After the repair service installing the coin comparator (sample coin in place) I still do not have a green light on the comparator.  I placed my cell phone inside the slot machine and recorded video of the comparator led status and once the reels reset after power on the comparator LED turns green.
2.    I tried the small white button on the optics board to manually add credits to the machine.  Does not work. No credits registered when pressing the white button.
3.   Using the “look here first” IGT S+ Frequently Asked Questions (FAQs) and how-to-guides” section on Newlifegames.com I was able to get into the Input Tests and found that 12_1 CoinC would not register a coin. I did this test by removing the comparator and using a popsicle stick to check the sensors.  11_1 CoinB tested good.  I verified this test by passing a coin into the machine as in normal operation from the coin in drop slot  and still got no signal on 12_1 CoinC .
4.   I ordered a refurbished & tested 10pin Optic Board from K*Lar and installed it.  Rerunning the Input Tests I get good signal on 11_1 and 12_1 but I do not receive any credits from pressing the white button on the optics board.
5.   I’ve ran through all of the input/output and sound tests without any errors.
6.   I removed the mother board from the machine and inspected for any burned traces, components or other visual issues.  No visible issues found.
7.   I’ve traced the wiring bundles from the coin optics/comparator back to the mother board with no wares pots or broken wires seen.

Thank you!  Ikelly208

[jay]

Great run down of what you have done and the results.

Given that your reel spin when you close the door - we can rule out door optics.
Since your getting the insert coin light on this also shows that your door optics are in good shape.

Initially I would say your coin optics are dead but you recently replaced them.
One thing that occasionally happens with coin comparators is that the sample coin stops being a good sample and a fresh coin helps.
If the coin is being rejected by the coin comparator then the optics don't matter....

However !! Given that the optic test button is doing nothing I would say that this sounds more like your optics are not getting power.
This would lead me to believe that you need to check the fuses. With the machine off - pull each fuse and use a meter set to resistance to test connectivity
 in the fuse. Sometimes they look good but are not.

I would also follow the wiring harness and make sure its plugged in properly at both ends.

[Jim]

the optic test consists of three optics, 10-1, 11-1 and 12-1.  all three have to work in order for the unit to establish a credit.

as for the white switch, you may have to keep pressing it many times, sometimes it doesn't get used much so the internal contacts don't make the first couple times ,  flick it using your finger nail several times, this may get it to work, also while in test 11-1, besides checking the optic you can also check the switch with the 11-1 test.  its the only test that the switch works with, not 10-1 or 12-1.

Hope this helps.

Jim

[ikelly208]

Thank you Jay and Jim for your quick responses !!

Jay:
Thank you for your suggestions !   I just now checked all of the items you suggested.  I have replaced the sample coin a few times thinking I may have an old vs new coin or something
 funny there but this did not resolve the issue (coin into hopper no credit).
I was able to remove each of the 3 fuses on the rear board behind the hopper.  Each fuse looked intact with no broken wire or burn marks.  Each fuse past the multimeter continuity test.
I removed, inspected and reseated each connector from the comparator and optics board back to the mother board.  I did not see any burn marks, frayed wires or backed out pins. 

Jim:
Thank you for your suggestions!  Excellent call out !  I did not know that the optics board white button could be tested within input test 11_1.  I put the machine in test mode and pressing the optics white button DID toggle 11_1 to 0 !  so that feels like a win for the optics board functionality/voltage.
Once I was out of input test mode I reset the machine again and I pressed the optics board white button multiple times and the machine did not register any credits.
That test got me thinking so I paced my cell phone inside on video mode to record the status of the comparitors LED after a restart.  Post restart/reel spins the coin comparator LED does turn green.
I was able to capture this on video: https://www.youtube.com/shorts/XQ8sqMCM6n0

I reset the machine again this time with the external coin tray removed so I could reach up inside the machine and press the optics board white button with the main door closed.  After the machine reset and I verified the comparator LED was GREEN, then reached up inside the machine and pressed the optics board white button.  The machine still did not register any credits for white button presses,  but after many more white button presses the machine threw an error code 21.
The error code sticker inside the door states that error code 21: Coin In Tilt.  To me this seem like the optics board white button is sending some sort of signal as this is the first error code I’ve received during this troubleshooting process.

Using the S Plus Diagnostic Flip Cards I found on NewLifeGames.com in the IGT S+ FAQs page I went back through the coin in input tests 10, 11, 12.

I was not able to get Coin in A: 10_1 to toggle to Zero when inserting a coin simulating normal game play with the door open or closed.  In both an open main door and closed main door scenario a coin dropped into the coin slot, through the comparitor  and out to the external tray and the winner paid display reads a constant: 10_1.  This may still point to a comparitor issue unless I’m performing the Coin in A: 10_1 test incorrectly.  You stated in your response that all three coin in tests 10, 11, 12 need to work to establish credit.   Do you have a procedure on how to execute coin in A 10_1 correctly?

Input tests 11_1 and 12_1 both toggled to Zero when inserting a popsicle stick into the optics board coin path.
And for good measure test 13 toggled repeatedly from 1 to Zreo with the main door fully closed.

On a side note as I continue to press the white test button on the mother board to step through all of the test when I get to selftest page “6” in the Coins Played window it displays 100.
Reading the IGT S-plus owners manual I have it speaks to self test “6” as displaying the current denomination setting in cents.  100 would = a dollar.  My machine is a 2 coin $0.25 machine
Maybe I'm reading the denomination setting wrong but would the denomination set to $1 have the optics board looking for a larger dollar coin vs a quarter and cause the system to not register coin to credit? 
I’m not sure if my chip configuration even allows for a denomination change but I thought I'd mention it as it seemed odd.  My current Game Prom is: IGT S+ Game Prom SP872 Type 0/1/4/5 27C512
 

Thank you again for all of your assistance!
Ikelly208

[jay]

Your going down the right route.
If you see the self tests changing then you are getting power.
Strange the white test button is not giving you a credit.
This should only work with the door open - albiet not many people would have tried to give it a credit with the door closed.

There is the popsicle stick test.
The optics work on A,B,C logic. There are 3 sensors. As the coin passes each optic beam is broken.
If the order is not ABC - top to bottom then you get the 21 error.
The intent is to prevent stringing (where someone puts a coin on a string and drops it and pulls it back up).
As soon as the optics don't happen in order you get the 21 error.

The popsicle stick test is to use a popsicle stick or a piece of cardboard cut roughly to the same dimensions and insert it into the coin slot and then you can see each optic change from a 1 to a 0 as it becomes blocked. I know you just replaced these but it almost sounds like they are bad... or perhaps something in the harness is shorted.

[Pitts256]

I had the same issue with an S+ machine.

1) The ABC Optics board wasn't functioning due to a shorted DS3 LED diode. Replaced the diode and the optics B & C tested good.
2) Coins would pass through the comparator and optics but would not register coins in. I tried a fix posted by Jim removing Q2 on the optics board which essentially disconnects the link between the comparator and optics board and places the "A" DS1 LED diode back online.  This worked and restored play. So this meant the comparator 12mSec pulse to the optics timing circuit wasn't there. I went back to the comparator and found the board voltages off and noisy, the filter capacitor C1 (Radial 220mf 35v) had failed. I replaced the cap, re-installed Q2 and all's good.

Here's a link to Jim's fix. "https://newlifegames.com/nlg/index.php?topic=35395.msg187531#msg187531"

Also I did a modification for the comparator issued by Coin Mechanisms to take heat generated from resistor R36 off of the capacitor C1. The mod was removing R36 from the topside of the board and placing it flush on the backside. This also gives a little more room for a slightly larger C1 cap than the original.


     

 

[Jim]

the best test for the optics is the Popsicle style test.  remove the coin comp., get in the test and preform each test, all three should toggle, when these all toggle and the cc-16 accepts the coin and presents it to the optics, in theory the machine should establish a credit when using a coin.

if 10-1 is not toggling then the optic is not seeing the beam being broken by the blockage from the the Popsicle stick.

when this happens, I remove either Q-2 or Q-4 from the optic board, its a surface mounted transistor, this will typically put the optic
back in the circuit, and THIS TYPICALLY WILL FIX 99 PERCENT  OF THE ISSUES WITH 10-1 NOT TOGGLING.

it has no other effect on the game play etc.

Hope this helps

Jim

   

[ikelly208]

Thanks Pitts256 & Jim for pointing out the Q2/Q4 optics board modification! 

I removed Q4 from my optics board and I now get 10_1 to toggle to 0 during the input test w/popsicle stick!
I verified the other optics 11_1 and 12_1 toggle correctly as they did before Q4 removal. Also verified 13_1 toggling with door closed for good measure.
(11_1 also toggles with the white optics board button)

After resetting the machine quarters going in still drop into the internal hopper and do not register any credits.

I opened the coin comparitor and inspected the PCB I didn't see any burn marks or fried components.   
The only other coin comparitor test I could think of was to put a different coin through the coin slot.
The comparitor rejected pennies, nickels and dimes into the external tray so it seems functional.

I'm not sure what step to take next.   Any further help you guys could provide would be greatly appreciated!!

[jay]

Does the credit button work ?

If not I am thinking that there I might be something up with the harness.
This is the second set of optics that the button is not working.
I have seen tons of gross, gooey and faulty optics. I have not run across any that the test button doesn’t work unless the whole board is pooched.

The fact that your board is recognizing the optics says it’s alive.

[ikelly208]

Sadly no.  Pressing the white button on the optics board will not put any credits onto the machine

The white button does work during  input test 11

I will reseat all of the connectors in the wiring harness from the coin optics back to the mother board just for good measure

[Stayouttadabunker]

What happens if you turn the coin sensitivity dial on the CC all the way counter-clockwise, and try dropping a coin thu it with the door closed?

            Or

with the dial turned all the way clockwise? 

I normally adjust by turning all the way counter-clockwise, then turning clockwise a 1/4 turn to get the sensitivity in the ballpark for quarters.

[ikelly208]

Thank you for the response Stayouttadabunker !

after powering on the machine, closing the door and waiting for the reels to reset :
CC turned full CCW,  Quarter is accepted into the internal hopper no credit registered.
CC turned full CW, Quarter rejects to external tray.

I then reset the machine and turned the CC halfway between full CCW and Full CW, quarter goes into the internal hopper no credit registered.


Further testing today:

I was able to get a new to me CC and Optics board online.
components came from sellers as "tested good".
Feels like swaptronics but I wanted to have new components in for the CC and Optics board to remove them as the source of the issue.

Putting the new to me CC and Optics into the system, I got the same error, quarter in going to the internal hopper.
(Yes, I put a new coin in the new to me CC)

I ran the new to me Optics board through the input tests and new Optics Board would not not toggle the 10_1 CoinA test (11_1w/popsicle stick and white button, 12_1, 13_1 all passed)
following Pitts256 and Jim's suggestion, i removed Q2 off the Optics Board.
10_1 now passes but same issue post system reboot, Quarter goes into the internal hopper and no credit issued.

i'm stumped on what to do next.
Any help would be greatly appreciated.
 

[jay]

3rd set of optics no white button working.

Order a new wiring harness.

[ikelly208]

Agreed.   Thanks Jay!

Could someone please help me locate a wire harness PN or a place where I could buy one
for my machine?

I have an IGT S+  Double Diamond  $0.25 2 coin Slot machine
The wiring harness  from the motherboard over to the comparitor is in two parts.   
PartA from mother board half way to comparitor has a tag on it that says: 600166 B ESAM 01/91
Part B from the half way point to comparitor has a tag on it that says: BLAYLOCKS Inc 05/91 600-102-00 REV D

I'm working to get pictures of the inside of my machine and the wiring harness labels up shortly.

Thanks again for the continued support guys !

[Stayouttadabunker]

I would ask NLG member Jim of Midwest Slots for a coin mech harness...his number's on the NLG Homepage.
If you have a multimeter, you could check the pins on your old Blaylocks harness for continuity? Follow the wire colors.

I hate to say it but we once had an S+ that kept "eating" quarters into the hopper, we were only able to resolve it by swapping out the MPU board.
Should you have a spare MPU board, throw the SP & SS chips onto it, and see if the machine registers a credit.
If not, let's hope it's just a bad wire on the harnessing? A lot cheaper than an MPU board.

I know it may of checked out ok but just for the heck of it, check the black ground wire on the short CC harness...>>>

[ikelly208]

Thanks for the response Stayouttadabunker!

I was able to check continuity on my wiring harness this morning from the CC and Optics board plugs all they way back to the MPU without a loss of signal.
I think my harness is OK.

This is my first machine so I don't have any spare parts other than my new CC and Optics. I'm currently searching the internet for am MPU board to swap in.

Please let me know if there is a good ITG S+ parts website I should be looking at, or if anyone on here has a MPU board for sale.

Thanks for all the help guys!


One other thing I don't think I got a response to in a previous post was a question about the Denomination setup for my machine:

as I continue to press the white test button on the MPU to step through all of the test when I get to selftest page “6” in the Coins Played window it displays 100.
Reading the IGT S-plus owners manual it speaks to self test “6” as displaying the current denomination setting in cents.  100 would = a dollar.  My machine is a 2 coin $0.25 machine.  shouldn't the display read 50 for $.50 or even 25 for $.25?
Maybe I'm reading the denomination setting wrong but would the denomination set to $1 have the optics board looking for a larger dollar coin vs a quarter and cause the system to not register coin to credit?
I’m not sure if my chip configuration even allows for a denomination change but I thought I'd mention it as it seemed odd.  My current Game Prom is: IGT S+ Game Prom SP872 Type 0/1/4/5 27C512

[Pitts256]

Your right, 100 represents $1. But this number only comes into play when you insert a bill into the validator. The way yours is configured now when you insert a 1 dollar bill into the validator you'll get 1 credit. I have a 1 dollar machine and I set mine for 10, a 1 dollar bill insert in the validator gives me 10 credits. When I sell a restored machine though I'll always set Option 6 to match the denomination displayed on the main door. You'll need a SET0015 Eprom chip to change this.

As far as the coin comparator...the CC16 (small coin) & CC33 (large coin) are connected to the same pins on the wire harness J51 plug. So either comparator will either accept or reject a coin, if accepted it will send a pulse to the ABC optics board turning on only "A" optics. If a coin successfully makes it through the comparator, the optics and into the hopper you should receive one credit.

Also I meant to ask if your ABC optics has the correct coin encoder. The quarter must block each eye as its passing through. See photo.
 

[ikelly208]

Thanks for the reply Pitts256!

my machined does not have a bill validator only a coin in slot so its odd that my denomination is set to 100.
 Is there instructions around for how to use the SET0015 Eprom you mentioned to change this denomination?

my machine previously functioned for months when i got it this past summer.
when replacing the coin optics for this troubleshooting i saw that the new optics board I received had the wider coin guide in it, so I used the original coin guide when replacing the optics board.   I just pulled the optics board to verify and it is the correct quarter sized guide. thank you for posting a picture of that piece!

[Pitts256]

No need to change the denomination on an S-Slot if you don't have a bill validator. As stated earlier any coin accepted is one credit.

The SET0015 will permit a denomination change and activate the bill validator. If you decide to purchase I'd recommend buying the SET0015 & Clear Chip w/instructions, they can be found on this website.

[ikelly208]

Hahaha no thanks I have enough problems with this machine without trying to mod it w/ a bill validator.