Burnt connection on S+

[kibble]

Why does this happen, is it just a bad connection or is something else going bad on my machine.
I replaced the molex connection this morning and all is working again but it still makes me wonder! Should I replace the pins that go into the molex also?
When i was playing on credits the leds on machine would just go out like it was resetting itself then i would get a 3100 error on the machine.
then just went out completely looked for hours late last night before looking here at NLG where i found the answer on where to look for the burnt connection.

[StatFreak]

It's a standard common issue covered many times, as you discovered.

If the Molex is damaged then replace it; otherwise you can just clean both the male and female contacts and you're good to go.

[channelmaniac]

That's common on pinballs too... the connections get a bit of oxidation on them and resistance builds up. This resistance causes heat which damages the spring tension of the contact and the plastic and it further contributes to the poor connection, resistance, and causes more heat. It's a cascade effect...

If you don't replace the pin then at least make sure it's clean and shiny to help keep the problem away longer.

[stayouttadabunker]

I agree with Statfreak and Channelmaniac...
These Molex receptor pins inside the housing were very cheap.
They only made contact with two sides on the male pins.

There are better receptor pins called trifurcon pins.
These special receptor pins "grab" four sides of the square male pins.
I like to get mine at mouser.com.

[kibble]

Thanks for the info, I think i will buy some of these pins next time I place an order with mouser.

I am going to take my machine out to the garage and clean it and go over all of the wiring since I have it apart now

you all have a Happy and safe Labor Day.    

[StatFreak]

   Remember, don't drink and repair!  
 




    ...or, "Drinking and repairing leads to more of both." 

[kibble]

  Remember, don't drink and repair!  
 




    ...or, "Drinking and repairing leads to more of both." 

and this  are for after i'm done today

[StatFreak]

and this  are for after i'm done today

So you're playing for high "Steaks". 

[stayouttadabunker]

A member recently wrote to me asking where to get these "trifurcon" pins on the S+ motherboard's 6-pin Molex housing.
He had a burned up ground pin in the Molex connector which is fairly common
because the original OEM IGT pins were the cheap ones that only touch one side of the male header pins.

That particular Molex housing has the numbers "09-50" stamped molded by the #6 pin position
and the letters "MX" by the #1 pin location.
Upon further  review, I realized that I earlier mistakenly posted that the the trifurcon pins grab 4 sides
of the upright mother header pins when in fact,  they only can possibly touch 3 sides of the male pins.
Makes sense as they're called "Trifurcon" pins - not "Quadfurcon" pins....
I apologize for my mistake...

Here are some links to the Trifurcon pin for the S+ Motherboard header Molex pins in question...>>>

http://www.molex.com/webdocs/datasheets/pdf/en-us/0008520113_CRIMP_TERMINALS.pdf

The 6-pin Molex 2139 series  .156 CL housings.
Not needed if the original housing isn't melted...just change out the pins really...>>>

http://www.molex.com/pdm_docs/sd/009503061_sd.pdf

[Ron (r273)]

I'm sure glad you clarified that Bunker. I been losing sleep over that not being a 4 sided
pin when I knew it was three. 

Just kidding!..................................... Thanks for setting us straight. 

Ron (r273)

[shortrackskater]

So, for my S plus collection, should I just check and clean (good contact cleaner or something else...see * below)  those original connectors as preventative maintenance? Would that keep them good for life if done once or twice or should I just replace them with the "better, tighter, females," so to speak?   

* And this brings about another question. If those pins are filed or even lightly scrubbed, does this remove off any kind of protective coating, which then would actually cause more oxidation in the long run? This was on ongoing issue with EM machines that I couldn't seem to resolve either. 

[knagl]

My opinion is "if it ain't broke...", but others might have a different opinion.

[stayouttadabunker]

STS,
You have a valid point and I do agree with you.
I'd like to add that while using contact cleaner removes the oxidization, they put a chemical in it
that also protects the metal from further damage.
I'm not sure what it is but I think it's that stuff they use in automotive metal contacts
in the firewall between the engine and the dashboard?

Brushing or filing the male pins alone isn't a good idea if you don't add protection.
What about the female receptor pins?
How does one get inside one of those?
As an Ironworker for over 20 years, I don't recall any acetylene torch tip cleaners being square?


I also agree with knagl's opinion...>>>  "if it ain't broke..." 

[Buzz]

Kevin/Mark  I guess there is two ways of looking at it. I have a couple of spare S+ mother boards that already have the mod done to them, just waiting for a S+ to come through the door. How long does it take to change out a S+ mother board, 5 minutes ?? 

[Foster]

The Connectors in that housing can be released easily with a small screwdriver.
I have done it a couple times on my S+.
Which will allow a better cleaning and minor bending of the connectors so they make tighter contact with the pins on the motherboard.

[azgamingslots]

cleaning the connections is only a temporary fix, the problem comes back in a short time.

 i think the heat weakens the strength of the metal, to fix, either the internal pin must be replaced or i usually cut off the plug, solder wires directly to motherboard.  tip: insert shrink tubing (to wires -to insulate) -must be done before soldering them on.  -since there is another plug on the power supply end, components can still be separated in the future.