IGT S+ lights up but LED doesn’t (update: Did set15, DBV mostly works!!)

[Kfrankie]

 Hello – I just recently purchased S+ dated 9/1992 3 reel.  From what I can see, the interior set up is a little unusual because the motherboard is located on the left side and not in the back. I have seen a couple of topics where the LED light does not come on, and ultimately the problem is a burned out plug going from the power supply to the motherboard. Unfortunately, with this left side MPU set up, there is not a similar connector that I can find. It appears that the connection is some sort of a 20 pin single row plug.  I’m concerned that the power supply is a problem, because don’t think the MPU is receiving power from it.  Unfortunately, I don’t know how to test the board because there are no test points. And it’s behind a metal plate so I can’t test it when the power is on. Nor can I test the power supply because it’s actually in the back behind the hopper and again there’s no test points to use. When I turn the power on, the reels do have some slight resistance, which gives me hope that maybe the power supply is working.

If I don’t fix this machine, my wife is going to kill me for buying it. I’m actually storing at my mom‘s house now. Any ideas?  I can’t attach a photo from my phone, keeps telling me the file is too large

[Chris-socal]

Im sure someone will jump in and give some advice, S+ machines are quite robust. However it very well could be a problem with the PS. Well worth investing in, they are good machines, albeit 35 years old!
Regarding posting an image, you need to do something to compress the image, some users email the pictures to themselves and let the email program optimize. Each individual image needs to be 1Mb or less, 5 images allowed per post. I suspect most techy people here will need to see a picture or two in order to weigh in.

Did you test voltage on the backup battery on the board?

Chris

[Kfrankie]

Thank you. I installed/soldered a new 3.6 volt lithium battery yesterday.  Tested resistance with a multimeter and all is well.  But can’t test the voltage when the board is installed with power on because of the metal front plate. Are you aware of a way to test the voltage of the motherboard?

[Kfrankie]

Here is a pic of the cables next to the side motherboard. I see the six or eight pin connector that is commonly burned out when doing the back installation of the motherboard. I inspected it yesterday. It’s not burned out. Do you know how I can test the voltage to the motherboard while powered up?

[Kfrankie]

Couple more. 1. Side Installation. 2.  Full view of machine. Also, the bill acceptor on the right is a making a clock like ticking noise when in power up the machine and continues until I turn it off.  The top fuse screw is loose/broken, but the middle and bottom fuses are in place and tested.

[Kfrankie]

Here is the power supply.  The top fuse is loose, I understand that only relates to some of the panel lights and not a critical component.  I put a multimeter on the back of the LED display board yesterday, and it is not receiving power. I’m think the power supply is the issue but no way to tell unless there’s test points I’m not seeing.  Strangely, when I turned the machine on, I could see one of the LED lights flash for a brief second and then turn off. Could any of this have to deal with the external Bill accepter clicking consistently as if it’s trying to turn on?

[Chris-socal]

Or the PS isn’t putting out sufficient power, which is extremely possible considering the age of the PS. As for testing the board, I don’t know anything about test points, maybe you could clip on to one of the ICs or maybe solder on to the 5v rail on the board.

There are several members who are very S+ literate, hopefully someone will jump in today.

Chris

[shortrackskater]

Are you calling this a mother board? This is the MPU or CPU, not the mother board - just for clarification. 

[Kfrankie]

Yes, I know for Ballys it’s referred to as an MPU.  Thought IGT used “mother board,” just trying to get my lingo straight.

[Stayouttadabunker]

Slide out that coin hopper, place aside for now...you don't need it.
You need to get the display and MPU working first.
Make sure that the MPU is seated fully down onto the motherboard.
By the way, for IGT's and S+'s, the motherboard is that long circuit board that's mounted on the floor of the cabinet.

There are 3 fuses on that back panel above the power supply you need to check.
Pull out the power plug from the wall outlet 1st!
These fuses need to be all working and are, from top to bottom...>>>

6A
8A
6A
with the abbreviation "A" standing for the word "amps" or "amperage".

They need to be "Quick-Blow" type of fuses and contain a thin filament wire inside of the glass tube.
Push in and twist counter-clockwise and pull out to inspect them.
They can be bought at any auto parts stores.
That top 6A fuse controls the power going to the reel glass panel display that shows you your credits on the machine as well as other information that you need to see whenever programming the machine.
I would say that it IS a critical component of your slot machine, wouldn't you?
Make sure all three fuses are working by testing for continuity with a digital multimeter, such as this one in this link I've attached for you below....>>>

https://www.harborfreight.com/7-function-digital-multimeter-59434.html

[Kfrankie]

Thanks for the response.  Now I know what the motherboard refers to… I believe that the mpu is securly seated.  I have also checked each of the three fuses for continuity and none of them are blown. When I say they’re not critical what I assumed not for the purpose of troubleshooting. But if it’s the reel glass LED then that is critical. The top fuse screw is not working, so that fuse is not being held in right now. I assume this may be the issue with the LED not lighting (assuming power is reach this fuse)? I will switch the bottom fuse holder to hold in that top fuse. I understand that the middle fuse relates to some of the other components that are not functioning.

FYI-  also learned that this version of the S+ was an early release with the MPU mounted on the left side. This model also uses a transformer, and does not have a “power supply” like subsequent S+ models. Here is a photo of the transformer on the left. To right is a “relay?” Apologize if my terminology is a bit off, I’m learning, but don’t have my mind wrapped around these concepts all that well at this point. I’d like to make this a hobby, and am willing to make a monetary contribution to this board even if we can’t get this thing to work.

[Stayouttadabunker]

Your top photo in Reply#4, is showing the MPU NOT being seated at all.
There shouldn't be such a big space/hole between the top of the frame enclosure that it slides down into, and the top of the MPU.

Secondly, your assumption, in that the display being related to the top 6 amp fuse, is correct.
You need to repair that top fuse holder, before we move on.

What is wrong with it?
Is the cap or main body cracked?
If so, take apart the fuse panel and see what needs to be done to repair it.
Pretty sure you can find a panel-mount fuse holder on places like Amazon.

[Kfrankie]

Thanks again for the input.  For seating the mpu, I’ve taken it out and put it back in several times. When I take it out, it feels like it’s pulling out of the sockets.  But I have not forced it down really hard when reinstalling it.  I’ll try that.

For the fuse screw cap, there’s a metal tab near the rim that’s supposed to prevent the screw from popping back out, but that tab has broken. I wasn’t sure what to order and that was going to be my next question because there’s quite a bit out there. Thanks for that.  I’m currently storing the machine at my mother’s house, and I go there every Sunday-Monday to watch over her.  I’ll be back on Sunday afternoon to try out a few ideas from you folks. Also have the new transformer ordered and arriving there hopefully on Saturday.

[Kfrankie]

Your top photo in Reply#4, is showing the MPU NOT being seated at all.
There shouldn't be such a big space/hole between the top of the frame enclosure that it slides down into, and the top of the MPU.

Secondly, your assumption, in that the display being related to the top 6 amp fuse, is correct.
You need to repair that top fuse holder, before we move on.

What is wrong with it?
Is the cap or main body cracked?
If so, take apart the fuse panel and see what needs to be done to repair it.
Pretty sure you can find a panel-mount fuse holder on places like Amazon.

So I found a photo in another thread of an S+ machine from 1989 with the MPU mounted on the left side of the cabinet. It appears that this one is pushed much further down into the frame then mine is.  Perhaps it’s the silver tabs on the side that are preventing me from pushing it down further because it’s misaligned.  I remember when I picked the machine up a few days ago. The first thing I did was ask the guy to remove the MPU and show me that the battery was missing so I could confirm that that was actually the problem and he did that. He may not have put it back incorrectly the first time around when he tried to start it up, and I may not have put it incorrectly again when I’ve removed it several times in the last few days. I won’t have access to the machine until Sunday because I’m storing it at my mom’s house.  If this was the problem I’ll feel both stupid and thrilled at the same time. Compare:

[lookes]

Looks like the wrong tray.

[Kfrankie]

Looks like the wrong tray.

Really? Don’t know how that would happen, or why someone would swap it out. The guy I bought it from told me it was booting up as of a couple months ago and showing the 12 fault battery code, and there was a photo in the Ad showing the machine with the code. When you say Tray, do you mean the vertical metal panel with the 5 plugs? So the photo from the other machine is a 1989 S+.  My machine has a manufacture date of 9/1992. I guess the tray could have changed?

[Stayouttadabunker]

Lookes means that vertical tray that the MPU circuit is mounted to...the tray with the big black knob.
They had a few different kinds...some were thinner on top - not as wide, but yours actually looks like about an inch or so higher?
I'm surprised you were able to get the pins under the MPU, to seat down into the motherboard headers.
The bottom photo with the small white label right next to the volume knob, shows the MPU board with the correct sized MPU tray.

[jay]

The MPU is mounted into a metal tray. 4/5 screws and a molex that connects to a transformer in the corner.

The trays are pretty universal however the tray from a slant top machine has metal wings on each side that prevent them from working (fitting) in an upright cabinet.
You can remove the board from the tray and use an angle grinder or perhaps a dremmel (the latter you will probably go through 12 disks) and cut them off. You remove the MPU board so you don't get iron filings all over the electronics.

On the S+ to change games you simply swap 2 chips along with glass and reel strips. On a PE+ (same vintage video poker) there are 7 chips to be swapped which is a PITA. Subsequently I have 6 boards for my PE+ and 3 for my S+ -  so I have bought trays for all of them. Some were from Slants and I have done the cutting of the wings on several of them.

The slant top if your not familar with them are the large sit down machines - you can pick them up a dime a dozen and sometimes people will pay you to take them away. They are just too big for home use and no one wants to carry them down a set of stairs to the basement casino. The parts however are mostly the same as what you have in a regular upright which makes them an in-expensive way to harvest parts. There are a couple of notable differences. Glass is an odd size and can't be used in uprights. The reel baskets are mounted at a different angle (noting that the name is slant-top) that means the NUB for mounting the reel strip is in the wrong place - you can ignore the nub or even file it off and use a sharpie (pen) to put a dot on the side of the reel basket to note where the knotch for the reel strip needs to line up. Electrically and how they fit inside a upright is the same. As noted above the MPUs are in a slightly different tray with wings. Buttons, floresent tubes, foresent starters, coin comparitors are all the same. Bill heads and cash cans are the same but the transport mech below are different.

Hope this helps.

[Kfrankie]

Lookes means that vertical tray that the MPU circuit is mounted to...the tray with the big black knob.
They had a few different kinds...some were thinner on top - not as wide, but yours actually looks like about an inch or so higher?
I'm surprised you were able to get the pins under the MPU, to seat down into the motherboard headers.
The bottom photo with the small white label right next to the volume knob, shows the MPU board with the correct sized MPU tray.

I think that may be my issue.  It’s not fully seated so that is causing my issues with the mpu not booting up.

[Kfrankie]

I went ahead and bought a new multimeter today for $30 at Harbor freight. The one you suggested that was $8 was all out, the employee told me that it was too popular so they ran out.