Bally e-series issues with MPU card AS-2978-3

[filounet]

Hello all !

I am new on this site and I saw that many of you are very aware of Bally e-series slots.
I have few Bally slots e-series 1000 and 2000 and I am still repairing some of them.
I have some issues with 2 machines, a E2238 and a E2090 and I hope you could help me:

•   I have good output voltages of transformers on the primary and secondary side
•   I have good voltages at the input and output regulation card
•   I have good voltages on I / O and MPU voltage regulators (model AS-2978-3 and AS-2978-7) for 12 and 5 volts
•   The triacs are ok at the I / O cards
•   I have no battery and trickle problems on the cards or deterioration
•   The machines work well at the mechanical level
•   I changed the phototransistors of the "real" cards
•   One machine does not display and the second just writes a "7"

I do not have electronic schemas of MPU cards of the AS-2978-3 and do not know where to look for the issue?
Can you help me?
Thanks for your help
Filounet 

[Amechanic]

Hi and welcome to NLG...   

I see you say you have two voltages, 5 & 12, But I don't see you saying anything about the voltages off the Power Supply? You should have 5V, 7.5V and 10V off the 3 test loops. One big problem with these games are that the PS plug looses it's connection with tarnished pins and crimp connections. You want to check the PS plug for burnt areas on the plug.. The other thing to check is the condition of the ribbon cables ends that connects the IO and MPU. The pins get bent or broken off. Also check the plug on your doors display for the same.. The game should power up and play without a battery..

[Badbaud]

Hello all !

I am new on this site and I saw that many of you are very aware of Bally e-series slots.
I have few Bally slots e-series 1000 and 2000 and I am still repairing some of them.
I have some issues with 2 machines, a E2238 and a E2090 and I hope you could help me:

•   I have good output voltages of transformers on the primary and secondary side
•   I have good voltages at the input and output regulation card
•   I have good voltages on I / O and MPU voltage regulators (model AS-2978-3 and AS-2978-7) for 12 and 5 volts
•   The triacs are ok at the I / O cards
•   I have no battery and trickle problems on the cards or deterioration
•   The machines work well at the mechanical level
•   I changed the phototransistors of the "real" cards
•   One machine does not display and the second just writes a "7"

I do not have electronic schemas of MPU cards of the AS-2978-3 and do not know where to look for the issue?
Can you help me?
Thanks for your help
Filounet 

PM me and I can give you a drop box link to download schematics for the E-series.
Badbaud

[filounet]

Hi and thank you for you reactivity 
 I already controlled 5V, 7.5V and 10V out of the 3 test loops and it's OK
What’s the PS plug? 
The plug on your door is ok too
Thank you and have a good day
Filounet

[Amechanic]

The 20 pin header molex plug on the power supply (PS). The solder joints on the that header pin connection develop cold solder joint connections. Plus the crimp connections inside that plug tarnish and loose there connection. If your machine has the newer style plug where the wires are crimped to the plug at a 90 degree angle instead of straight in, well that newer styles junk. I don’t know the name of the newer style plug, but the ones I’ve seen in the 20 pin style are yellow in color and they have a black cap on the plug.

[filounet]

I'm sorry but I do not understand or search on my two cards IO and MPU?
Filounet

[Amechanic]

I see one major problem. Your rib looks cable that connects the IO board and the IO Board is installed upside down!! The red line or side of the ribbon cable faces down towards the closest side of the boards. Carefully remove this ribbon cable and turn it over so the red faced down on BOTH ENDS.. The pins on these plugs are very fragile so be careful. I’m guessing someone replaced this one because it’s so long.

[Amechanic]

This is the IO Board side. Same thing here, Red side down.. To do this you will have to fold the cable back over the plug when installed. You will have to do it on both ends.

[Amechanic]

Here are 2 pictures I saved of the correct way.

[filounet]

Ok it's done but now the coils do not stop working!   

[Amechanic]

I had that happen before, but I don’t remember exactly what the problem was? I think it was the capacitor that control the yellow relay. Have you taken the ram board off the MPU? You might want to do that and inspect the ram boards edge connectors for any acid damage.

[filounet]

yes I have already checked the memory card with the multimeter

[Badbaud]

Reverse the cable ONLY on the I/O board this time.

[filounet]

Hi,

the coils don't stop even by reversing the connection
Have a nice day

[Badbaud]

The coils not stopping is usually caused by the ribbon cable from the MPU board to the I/O board being plugged in backwards.

[Toyguy]

I don't have one of these machines, but the safest thing to do is look at the boards and identify pin 1.  It looks like Bally may be marking them with a white dot from all of the pictures.  The red stripe goes to pin 1.  You should also try to verify if the original Bally-provided cable was a straight through ribbon cable, since yours appears to not be original.  Ribbon cables can be made with a twist in some of the wires by splitting the cable and turning a piece of it 180 degrees.  You'll probably need an owner who has one to verify that for you.


First thing though, I'd locate pin 1 and match up the red stripe - see what happens once that's done.

[filounet]

it's true this cable comes from another machine but I'm sure it works
There is no pin 1 visible
I tested the 2 cards with the cable on each side and all the welds sound so which validates the cable and the welds in and out, it's not the right track for me
By plugging up the two red markers I do not have the problem even if the machine does not work in the end

[Amechanic]

I have had bad MPU boards do the solenoid chatter before. Normally the number one pin is marked with a red strip on the ribbon cable or a dot on the plug. These face down in these Bally  E-Series machines.

[Badbaud]

Do you have a scope? There is a 2 uF cap used to regulate the output of the 5V regulators and when it gets weak it allows the 5V to pulse with noise.

[filounet]

Hi

I reconnected my original red / red cable at the bottom and more reel noise
I still have the code 7 of departure
Do you have the code for the 2 uF capacitor on the schema?

Thank you for your help
Filounet