T2 G.I. Fuse getting hot.

Grbgemen

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I have been working on a T2. G.I. connector J115 had burnt and was hacked into three connectors along with a half ass header. J120 was also burnt. I have replaced both connectors and headers. Had to fix a few through hole connections on J115 with a wire stitch.

Problem is that Fuse F108 is getting really hot. If all the bulbs are put in the G.I. string, the fuse eventually blows. I have checked visually for any wires shorting on anything. Visually inspected each socket and all look good. Used the trick from pinrepair and removed all the bulbs from the string and tested at the fuse with a good bulb. Bulb did not light which should mean no shorts on the playfield.

Right now I have about 10 bulbs from this string removed. They are all in the backbox. The fuse is not hot with these removed. Maybe a tad warm. Using brand new #47 bulbs on the playfield and new #555 on the backglass(well when they were installed). I have done all the checks on pinrepair. Each pin has proper [FONT=verdana,arial,helv,helvetica][SIZE=-1]continuity[/SIZE][/FONT] to its corresponding fuses or triacs.

I did notice that I was getting about 7.9v AC when I tested the G.I. string associated with F108. I tested another string and was also getting 7.9v AC. Would this be my issue? Pinrepair says 6.3v to 7.3v. Would that be a bad transformer in the bottom of the cabinet?
 
I already did the power settings but could not find where to reduce the G.I. level.

LEDs is a good idea but I want to figure out what is wrong. With some of the backglass bulbs installed, the fuse is so hot that you cant touch it for more than a second.
 
There is a known design flaw in the game that puts too much voltage over some of those connectors.

It could also be an issue with a bad solder joint. You could try re-flowing the solder joints on the fuse holder.
 
You replaced the male header pin connectors on the board? You also replaced the female mates in the harness?

Great Plains Electronics sells the black (high heat) Molex connectors for the General Illumination circuit.
 
Yes, headers replaced along with the connectors. New trifurcon pins.

Could it be a bad fuse holder? The one clip of the fuse holder was a little brown on the inside. I sanded it off. Did not think that would really make a difference though.

The plug in the bottom of the cabinet coming off the transformer has not been replaced but it does not appear burnt at all.
 
Fuse should be a 5 amp slow-blow type. Yes, the fuseholder can tarnish and have resistance that would cause it to heat up.

Also, check the jumper settings of your power input plug at the power transformer. When I uncrated new pinball machines, the factory routinely set the jumpers to 115 volt operation. Typical line voltage here in Olympia, Washington is 125 volts. Naturally I reset the jumpers to match the line voltage we have here. This is described in your manual. You'll need a Molex .093 pin extractor to swap the jumpers around in the connector.
 
Fuse is definitely 5amp slo. already have replaced it numerous times when I was trying to diagnose the problem.

Will look into the fuse holder and jumpers.
 
What about the connector that comes from the Transformer itself? The last T2 I worked on had that burned to a crisp as well and that could be adding heat to the equation if it is toasty and adding resistance...
 
What about the connector that comes from the Transformer itself? The last T2 I worked on had that burned to a crisp as well and that could be adding heat to the equation if it is toasty and adding resistance...

Oh yes I've seen that connector burnt as well.
 
Like i mentioned above, the main connector in the bottom of the cab has not been replaced but when I looked at it, it was not burnt at all.

I imagine I will re-pin the connector, replace the fuse holder, and then see what happens.
 
Do the GI String light up individually in test? If the connectors are not wired correctly you can have have 2 strings on the same fuse which will then blow as it heats up.
 
hmm good point. Will check into that also. Will be stopping by where the pin is located today and will report back.
 
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