Lower GI fuse blowing on funhouse. Short help

beerorkid

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During my full shopping of a funhouse the lower GI keeps blowing. It takes a 5 amp fuse, but the Bob Roberts 3 amp fuse breaker has worked great.

There are times where I mess with lamp sockets and it will go for 40 minutes of game play before it blows the breaker / fuse. Sometimes it is immediate it blows the fuse. I have removed a bulb at a time on all of the GI chain and it is the same story.

couple questions. Keep in mind it blows the breaker and 5 amp fuses within 40 minutes.

1. I am pretty sure it is a short, but could it be a thing with the header pins and connectors?

2. Do I need to unsolder the sockets to isolate this?

It is making me hate pinball and I want to cry. I am going insaner. I have some new sockets on the way and have everything to change the headers and connectors.
 
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i would check and make sure that a wire hasnt been bumped, where maybe vibration from coils firing makes it move to make contact with ground and short causing the fuse to blow, if removing the bulbs changed nothing then yes you will have to do some soldering.
 
Ok .so are you saying that no matter where the blub is plugged in that it will blow the fuse.No matter what, it sounds like a wire problem.You say after you play with it it sometimes will go 40 min before the fuse pops. Im guessing that there is a wire rubbing somewhere under the playfield or the wire connecter . Im just thinking out loud so forgive me if I sound stupid.
 
The general illumination lamp circuit uses several 5 amp SLO-BLO fuses. Be sure you are using the correct fuses.

Be sure ALL the lighting circuit female connectors AND the male header pins are in good clean condition. Also, check the soldering of those male header pins.

Once in a while the actual fuseholders on the circuit board will go bad from tarnished contacts and warrant replacement.
 
Where I am at now is thinking one of the lamp sockets is shorting somehow.

Also the main GI power connector is IDC and I am ready to pull the board to put in the newer headers and connectors. My main Q is if bad connections will blow the lower Gi fuse.

I know just pulling the bulbs is not enough to clear a short.

So I am asking if it could be on the board before I go insane.

As to Ken, that is where I am going. Replacing the connectors to see if it fixes it. Previous posts said to test the solenoids and I had no issues.

I had a guy fix the Gi power to the board and install headers and connectors on my BOP. It solved a similar issue. I am hoping it solves this one as well.

5531441220_3ac5a3d38b_z.jpg
 
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Those IDC connectors are notorious for poor connections. Since Williams runs the lighting circuit pretty close to the upper limits of the connector specifications, they tend to burn & develop resistance. This in turn causes more burning and power surging which blows the fuse after a while.

If you had a shorted lamp socket or even a shorted bulb itself, the fuse would blow immediately or within a few seconds.

I'm betting you have bad connectors.
 
Those IDC connectors are notorious for poor connections. Since Williams runs the lighting circuit pretty close to the upper limits of the connector specifications, they tend to burn & develop resistance. This in turn causes more burning and power surging which blows the fuse after a while.

If you had a shorted lamp socket or even a shorted bulb itself, the fuse would blow immediately or within a few seconds.

I'm betting you have bad connectors.

I will report late tomorrow evening. I am pretty sure this might be the issue after the issue arising after I had reseated those connections many times.

I agree that a short would be pretty apparent. I have messed very little with the under bits of the machine.

Thanks Ken.
 
I replace the female IDC connectors with conventional Molex wafer housings and trifurcon crimp terminals. The gives much better connections. Granted this takes more time to do, but results in a more reliable connection.

Those IDC connectors are absolute crap.
 
Before I knew, I picked up the IDC box from pinball life, but made a proper order from GPE a week later. The hardest part was getting the correct crimper. Ended up finding a perfect one from home depot. One little groove on it is exactly what I needed. Why is it so hard to find a proper crimper?

Going to replace the main GI power connection and the one that powers the GI. In the pic above all the connectors are off and the board is ready to be pulled. I was going to replace them before I crawled to you guys to ask for some support.

I still really do not understand the ones where you need to put some connection between the front and back (Through connections). Why is the pin not enough to complete the connection?
 
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Think of the plated through hole connections and a connection being made on both sides of the board. The plating allows the connection to pass from the bottom side of the board to the top side. If the plated through hole breaks, then the connection is broke.

Installing a new header with a broken connection does no good. Sure you have a connection on the bottom side but connection to the top side is still broken. This is why you solder in a few strands of wire through the hole.

Pull the G.I. header and check each hole for broken connections with your meter. Fix any broken connections with a few strands of wire like mentioned above(Dont use too much or you wont be able to install the new header). Then install a new header and connector w/new pins.

Finally check and see if fuse blows.
 
Replaced the IDC with a molex connector.

Still blowing

Desperate I get the breaker flowing again and dig around under the playfield while it is on. Just slightly touching wires. Nothing happens.

I close the coin door because I am giving up and the lower GI flicker.

I rock the game side to side and the GI flickers.

It was the socket for the coin slot lights that was slightly bumping.

I am really glad I figured it out finally, but am so bummed at how long it took me to get that right.
 
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