Reel Stop Board Professionally Rebuilt, but still Won't Work. Mainboard Issue

[SKYNET2023]

I had a faulty stop board on my slot machine which kept blowing fuses.

Considering that I am not well acquainted with board repair, I found a repair service on eBay that services the reel stop board.

After I got the serviced stop board back, I hooked it up and noticed some strange behavior...

When all 4 wires were plugged in, the 'insert coin' light which normally blinks would not engage, hence I could not spin the reels. The only way the 'insert coin' light would engage is if I disconnected the plug with 2 wires on the reel stop board.

Aside from the 'insert coin' light acting up, the reel also does not stop when the buttons are pushed.

Another strange thing I noticed, is if the game is in attract mode and the reel buttons are pushed, the mainboard shows indicator lights for the second and third buttons but not the first.

I mailed back the reel stop board, assuming something was wrong with the repair, however, when the tech received the return, he sent me a video showing that the reel stop board was functioning perfectly fine.

With that being said, I have. some other kind of issue. I am suspecting the main board has some type of fault. But I do not really know where to begin or what to look for to get to the bottom of this issue.

Any help or advice would be greatly appreciated.

[Drunkenclam]

Well it seems odd. that you only get a signal from the second and third button.

I would start by looking at the first button. Some use photo interuptor sensors and the IR led or receiver goes bad. And then extend to any other input switch.

[SKYNET2023]

Thanks for the suggestion, I appreciate it.

I took the button assembly apart, and I could not notice anything visually wrong with the button sensors. What should I be looking for? Maybe I can run some type of test on a multimeter?

You might be on to something, because the 'start' light wont light up when both the reel stop board and button board are connected. Disconnecting either one of the two results in the 'start' light working again.

Aside from the potential to run some tests on the stop button board to see if something is shorted out, I found a replacement button board assembly which should fit my machine on eBay.

[SKYNET2023]

You were right!

I desoldered the photo sensor switch from button one and sure enough, the 'start' light engaged and buttons two and three work!

Looks like I need a new switch. Would you happen to know what the part number is or where I can find one?

Well it seems odd. that you only get a signal from the second and third button.

I would start by looking at the first button. Some use photo interuptor sensors and the IR led or receiver goes bad. And then extend to any other input switch.

[Drunkenclam]

Unfortuatley not. It will be a case of checking the sensor for a make and model number. or delving into an online store and checking the spec/ hole pattern. or hunting around for a second had switch/sensor board.

[SKYNET2023]

Thanks.

There is no model number or any writing on the sensor itself. However, a search on Google for 'electrocoin parts photo sensor' found me what looks like the correct part. I don't know about the sensor width yet, but its the only photo sensor with 5 pins like the one on my button board I could find.

https://www.digikey.com/en/products/...SABEgKHZfD_BwE


I was also able to locate a button board on eBay which looks nearly identical, the screw pattern is the same but the part number of the board, and the location of the connector varies.

https://www.ebay.com/itm/284829113432

Unfortatley not. It will be a case of checking the sensor for a make and model number. or delving into an online store and checking the spec/ hole pattern. or hunting around for a second had switch/sensor board.

[Drunkenclam]

I don't think you specified that make and modle of your machine. But I guess by that ebay page. its a type that all the all the sensors are on one board.


My parts place (UK) has loads of 5 pin versions. So the size of the towers and slot width would help. Also check the input voltage and which pin it goes to

https://uk.farnell.com/omron/ee-sx40...t=interrupters
https://uk.farnell.com/omron/ee-sx30...t=interrupters
https://uk.farnell.com/omron-electro...t=interrupters


If you can find the right part number there. You might be able to search for the part number locally.