S+ with no display

[Badbaud]

The one power supply that has not been mentioned is the one on the MPU board.

The 6 pin Molex header may be corroded or you have a collapsed pin inside the header.

I have never seen a transformer (or power supply as some call it) go bad in a S+.

[therockinelvis]

If it is bad, this will be the first for me. Having those voltages lets me check it. Glad you said something about the ps on the board tray. I would have taken a board only. And YES to everyone that reads this post, YOU CAN UNPLUG BOTH ENDS OF DISPLAY AND MACHINE WILL STILL PLAY.  Display is not part of game working.

[Buzz]

I think after I drove 200 hundrer miles and replaced the power supply, the display, the MPU, and even the hopper and the machine still doesn't work I'd take a good long look at the main door optics.

[therockinelvis]

Wouldn't the optics still let the coin played light up? I've been playing with a test machine and can't duplicate this. It appears that the only low voltage is in the 6 wire cable with 24, 8, and 7 vac. Not sure which voltage goes to what. I'm feeling like it is going to be motherboard problem or the transformer on MPU. Taking a pile of parts just in case. I tried to get him to bring machine to me and I would change his kit to another machine and send him home. Me going to him is easier than him finding someone to help him load it.

[Buzz]

Door closed, Door open but what the hell, lets do it your way.

[therockinelvis]

Buzz, I am not disagreeing with you. Please don't get angry with me, I respect your diagnostics. The machine I'm talking about has no display and does not get ready for game. Door open or closed. He leaves the machine on 24/7. Maybe this will help, about 3 weeks before this he found the machine with code 61 and he had not turned the machine off. I had him do the clear for 61 and all was good until this. I'm taking a known good MPU, motherboard, and power supply. Tuesday I will be in front of the machine and will report back.

[Badbaud]

I have seen a sticky 61 be caused by a bad EEPROM on the backplane board.

[rickhunter]

Yes, it can be.  If a clear does not solve it, that is the next step to take.

[therockinelvis]

So, are you saying to try a clear first?

[Jim]

The S+ machine is a solid working machine, very few problems and EXTREMELY easy to repair. In over 15 years of working on these machines I have never had a Power Supply Module bad. there have been coins that got into that area and caused a fuse to blow, but outside of that an occasional fuse holder crack. The only parts in the module are the fuse holders, the terminal blocks, the inline filter, and the transformer and the plugs and connectors.  The only voltages that come out of this unit are the AC voltages, they are the 115 VAC connectors in the back, these all go to power the florescent lamps (black and white wires) the bigger plug on the back goes to the on/off switch assembly.  the two connectors on the side, one goes to the FAMOUS connector that fails all the time, the other goes to the the hopper SSR. (115vac to operate the hopper motor) the three AC voltages provided by the transformer are 24vac center tapped, 8vac and 7 vac. these voltages are provided to the motherboard to be distributed to all the units needing the required voltage. the 7 vac is used to provide an operating voltage for all the lamps in the machine #86 (inset coin lamp,coin accept lamp, denomination lamp. etc.)  #297,#555,or ?  switch button lamps. the 24 vac  is used to power the handle solenoid, used to power the step down transformer on the board tray to provide voltage to make the +5vdc that operate the logic on the main CPU board. the 8vac is used to power the circuit that establishes the voltage to hold the reels in place (stiff), it also provides the voltage Vb. This voltage runs alot of things in the machine, it is sent to the coin optics, and it is the primary voltage that runs the DISPLAY board. This voltage can be measured across the larger electrolytic cap on the display board, I think it is C6, you should be able to measure 8-10vdc across this cap.  In a recap of the above information, let me tell you what you could assume from this information.

If the reels are "STIFF"-  all three fuses are good, why?  one fuse controls the 115vac coming into the machine, if the florescent's are on, the 115vac has to be getting to the transformer to provide the voltages to make the voltage to hold the reels in place. the other two are used to make those voltages that hold the reels in place.  another way to check to see if your fuses are good (if you don't have a meter handy)  unloosen the fuse cap, one at a time and observe and listen what happens, the 115vac fuse un done, the flourescents go out, the 24vac fuse, the reels are not stiff, you hear a crackling noise in the speaker, the 8vac fuse, again the reels are not stiff and you hear a crackling noise from the speaker.
So basically we have tested all the voltages(AC) by just observing what is going on, we have tested some of the DC voltages (reels stiff) and if we measured the +Vb at the display then we know that all the voltages are good except the +5 vdc  and the +VUN . I would ASSUME that these are good as well. I have only seen two times that these voltages were bad, both times the voltage regulator was shorted and caused the diode that is in front of the regulator to drop off the board.

Fuses are very easy to check, right, WRONG.  Typically a blow fuse will show that it is bad, a blackened spot inside the glass and the wire is open, but what about the fuse that is not blackened? or the wire is not open?  I have seen the appearance look good but the fuse was bad. sometimes the wire will break open up underneath the metal ends of the fuse, not visible to the eye, the only good way to test the fuse is with a meter, or if you don't have a meter handy you could use a flashlight, un screw the end cap to get at the batteries, place the fuse on the end of the battery and put he other end of the fuse to the end cap and turn on the flashlight, if it comes on the fuse is good.

I have seen the one of two components that make up the +Vb voltage go bad, mainly the diode.

This should help you with your power supply problems. You should NEVER attempt to troubleshoot any electronics until you have determined that all your operating voltages are good, if not, you are just spinning your wheels.

The S+ machine has a built in set of diagnostics that will test EVERY function of that machine, when you use these tests it makes the machine very easy to determine what the problem is and helps to isolate to a sub assembly.

The biggest and most talked about problem area on this machine is the DOOR OPTICS.  there are two areas that cause this problem(outside of the wires being broke on the optics themselves) that is with the cash can door switch, two green wires that enter the back of the cash can area, these should always be spliced together, the other area is the belly door switch located in the upper left hand corner of the belly door, (most machine did not have this switch installed there is a jumper loop where it would have been installed) but if your machine has it, bypass (splice) it as well.
On the input test(diagnostic) test #13 will test the door optic , you will see a 1/0  alternating when you put the latch in the down position, it will stop when you lift it up, if it does this the optics are good.

Hope this helps

Jim     

   

[CommTech]

Jim, That is one thorough explanation! 
Great information!!!


 

[therockinelvis]

Thanks Jim, that was a mountain of information and I printed it for future reference. Like I said before, the machine on power up has stiff reels, cabinet lights, and that is it. No maiden spin or any display. I have always seen at least the coins played segment displayed open door or closed. That leads me to believe that something is preventing power at mpu. I will be in front of machine Tuesday and hopefully figure it out. I too am pretty much ruling out the power supply, but taking one just in case. Think I will reseat ALL plugs and see what happens. Once I check the voltages you gave I will try a different mpu then mother board.

[therockinelvis]

OK guys. It took me 2 hours but I got it going. Was about to give up. I couldn't help myself, I checked the voltage in 6 pin molex and all were good. Pulled board and put a spare in with other chips. Fired right up and after 61 and 65 stuff was good to go. Change SS and SP chips to new board and again 61 and 65 normal stuff. Then I needed to set the settings and BV so I opened the door and got 21. Very stumped because there is no coin in equipment in machine. Finally realized that just lifting the door latch the 21 would appear and close the latch it would clear. Ready to play I think. But because it is coinless and the BV needed to be set I couldn't go any further. Pulled the board and did a clear still the same. Right as I was about to give up in defeat, I decided to change the cmos. That took care of the 21 and set option and BV/denom. All is working as intended. So I guess long story short the board was causing the display and boot problem and then changing the cmos took care of the 21 issue.