S2000 displays netplex link is down/ missing parts

[702collector]

Newly acquired machine. Display passes self test then says netplex link is down. No LEDs are lit on mpu. Machine is missing power distribution board and ribbon cable. Also no wire harness to cabinet mounted I/O card. Battery is completely dead. Anyone see anything else missing?  It is a 5 star by the way. 3 reel 1 line 3 coin max

[702collector]

More pics

[702collector]

Machine

[Sunrise Side]

Make sure the power supply behind the reels is seated fully by moving to the right and the thumb screw on the left is turned in fully. Check the power cord in the bottom and make sure that is fully seated as well.

[702collector]

Ok here is the confusing part. Made sure the power supply behind the reels was tight. Checked voltage on backplane at lower left plug.
Black = 6VAC
RED = 0 VDC
Orange = 1VDC

Checked voltage on working s2000
Black =6VAC
Red =12VDC
Orange =24VDC

Swapped power supply from known working machine to non working machine
Black = 6VAC
Red = 0VDC
Orange = 1 VDC

[Stayouttadabunker]

The white 10-pin Molex connector on the lower right side of the backplane.

You want to measure the top single black wire coming out of that housing.
Then measure those red and orange wires by sticking into the back of the connector housing with the red multimeter probe.
Touch your black multimeter probe against the metal floor of the cabinet and let's see what you've got.

[702collector]

That’s exactly where I measured the voltage. Found an old post from you showing that. My voltage measurements are in the post directly above yours.

* sorry I said lower left I meant to say lower right

[702collector]

The known working power supply gives me the same outcome. The machine does not have a harness connected to the I/O card in the cabinet. Could this be the issue?

[RB]

The known working power supply gives me the same outcome. The machine does not have a harness connected to the I/O card in the cabinet. Could this be the issue?

If you are referring to the open 14 pin connector on the handle side of the I/O, that's only needed for backlit reels.

[702collector]

Thanks Ronald! That explains why one of my machines has the harness and the other one doesn’t.

[702collector]

Put the power supply in another machine and it works fine. Swapped in a known working backplane and same result. No lights on mpu and displays and netplex link is down. Do I break down and order a new mpu board?

[Tilt]

If the picture you posted is accurate then you have to be measuring your power supply outputs wrong.  The fluorescent lamps that light up the machine operate off of 25VDC from the main power supply.  You say it measures 1 VDC which can't be right if they are lit as shown in the picture 

[702collector]

Thanks Tilt! You gave me an idea so now hopefully someone can make since of this. We are measuring voltages where the power supply plugs into the backplane. So based off of your observations of the lights being lit I unplugged that connector and turned on the machine. The lights still come on. So my next question is does the power go through something else before it goes to the backplane? I measured the voltage at the connector when it was unplugged and still don’t have the 12 or 24 volts DC however the lights are still powered.

[Tilt]

The power for the fluorescent lamps splits off of the power supply connector and doesn't go through P13 to the motherboard to get to the lamps.  That same voltage should be at the connector on the motherboard though.  Put the negative lead of your multimeter on the metal interior of the cabinet and positive lead to the orange wire on P13 and you should see + 25VDC, the red should be +13VDC. 

I've attached a the wiring diagram for the power supply which may be helpful.

[RB]

Your backplane connectors have been messed with. Move J2 to J14. Move J3 to J2. There should be another connector somewhere that goes to J3. It will have a red +13v wire but no orange +25v.

[702collector]

The connector at J3 only has the red no orange. No other connectors. Maybe it’s missing?
The voltage just isn’t there at p13.
I’m not crazy. I’ve checked it multiple times in my working s2000. The voltage is matching what you say.
When I check it in the non working s2000 it might hit 5 or 6 VDC sometimes and slowly drops to 0.
Older post on the issue mostly poor at the power supply but I’ve put it in the other machine and it works.
Pulling my hair out on this one!

[RB]

Duh! 
I was looking at Bunker's picture not yours. Disregard. Your cabinet is an early one and possibly a Vision cabinet with the speakers inside the top box and no sub woofer I assume. I see no close up picture of your backplane connections.

[Tilt]

Pull J13 off of the motherboard and check voltages with it disconnected.  There may be a short somewhere causing the power supply to shut down?  It could only apply to the +13VDC side though, because the +25VDC must be up for the fluorescent lamps to light up.  If I pull J13 off of one of my S2000's I only have the fluorescent lamps lit, no LEDs on the MPU, but my VFD is also dead as in blank.  That's with a 5-5-2 display. 

[702collector]

You are onto something Tilt. With J13 disconnected orange hit 17Vdc then drops to 0. You can watch the voltage drop. Tried it several times and each time the voltage started lower but always dropped to zero.
The red shows negative voltage starting around-7 then goes to zero

[Tilt]

Hmmm.  None of that makes any sense.  Try a different meter, or maybe it needs new batteries?