IGT slot machine not working after pulling MPU with power on

[Dreibsl]

I have an IGT slot machine built in 1998 it was converted to token and was working fine. I was showing someone the insides of the Slot and they asked what the control board looked like and not thinking pulled the control board with out powering down before pulling it and put it back in. I then saw the power was still on on the machine. I shut it down and unplugged it. But when I power it back on the wheels don't orient themselves, the LED lights on the front don't light up. I have unplugged it and let it set over night and pulled the board. Re-installed the mother board and it still doesn't seem to boot up and run through start up. I don't know what to try next. Any help would be greatly appreciated. I used to be an electrician so I have to tools to check things on the motherboard I just don't know what to check or where to check to find out what the issue is. Thanks in advance. 

[Tilt]

Well I guess you found out rule #1 the hard way.  Never remove or install a component with the power on. 

Post a picture of your machine inside and out so we know what it is and can provide better assistance.  Pics have to be under 1mb to post, so resize as necessary to get under that limit.

[Dreibsl]

Here are some pictures

[jay]

IF your not getting lights it might be you knocked the main power feed. If so you got lucky here.
Directly behind the hopper is the small fixed motherboard that the MPU (what you are calling the control board).
On that small board is the a large molex in the middle. Wiggle or reseat the connection and see if anything changes

The other thing is to check each of the fuses for continuity using a multimeter.

[Tilt]

You have an IGT S+ machine.  Check the fuses and connectors like Jay suggested.  Did you get the MPU board fully seated when you re-installed it?  You should be able to feel it when the connectors mate and when it is fully seated. 

Do the fluorescent lamps work when it's turned on?

[Dreibsl]

The flourescent light do come on

[Stayouttadabunker]

...I used to be an electrician...

You must have gotten shocked a lot?   

Just kidding!

Once, I twisted a metal starter on an S Plus door panel fluorescent ballast....the cap broke, the wires inside touched and I went flying across the room. 

Check also to see if the reels have a fair amount of resistance with the power switch [ON].
They should be able to turn by hand, but are not completely free-wheeling.

Also, as you close the door latch, watch the [Coins Played] window on the display.
Whatever number is in there, should momentarily go out when the door latch goes down, then come back on after a second or two.

[Dreibsl]

All fuses are good. Connectors seem to be seated on the small board. MPU seems seated all the way down. Wheels don't have any resistance and free wheel. When i close the door the coins played is blank and never comes on.

[Rob in AK]

All fuses are good. Connectors seem to be seated on the small board. MPU seems seated all the way down. Wheels don't have any resistance and free wheel. When i close the door the coins played is blank and never comes on.

sounds like maybe the power connector might be the issue. http://newlifegames.com/nlg/index.php?topic=28443.0

[jay]

The power connector is the large molex I pointed out in my earlier post.
With the hopper out, power on. Wiggle, slightly lift, reseat, the connector and see if the lights pop on and the you will see no the reels slightly jump and visibly stiffen.

What happens is that the pins on this connector gets scorched and then they lose contact.
I use a white eraser and a pen knife to shine them up. Sometimes the power harness needs replacement (on this case you will see the molex visibly burnt/discoloured) but most of the time the clean up of the 30+ year old connector does the trick.  You of course do this cleanup with the power OFF. My leading theory here is that the minor arc’ing that occurs was likely on overdrive when you pulled the board with the power on.

[Dreibsl]

Oh you guys rock. It was the power connector. I wiggled the connector and the reels tighted up. Closed the door and it works now . Thanks so much for your assistance. Such a great forum.

[Tilt]

Glad you got it working again and that nothing got damaged  .  In the future make sure to turn off the power before removing any components.  Clean the pins on that connector with a pencil eraser and a few drops of Deox-it will help too.