My Demolition Man started blowing the line fuse. When I power it on, all four flippers engage and hold for a couple of seconds and the main fuse blows. If I power it on with the coin door open, it boots and then works fine after closing the door.
So you are powering up with coin door open when this happens? That is how I'm reading this because of you saying this-
Quoted from Yuckster:
If I power it on with the coin door closed, it boots and then works fine after closing the door.
Or on the second statement you mean open the closed.
I'm thinking you may have a interlock switch on coin door that wires are pinching or shorting out.
Time to find schematics and see if it's plausible.
Sorry, I mistyped. It only happens when the coin door is closed. If I boot it with the coin door open, it works fine.
This has an interlock switch on coin door?
Thinking you would then need to check that and every circuit it opens (high voltage for coils)
The game functions correctly if I close the coin door after it boots. But if the coin door is closed when the machine is powered on, it fires all four flippers and holds them for a couple of seconds until the fuse blows. I don’t believe that the fuse blowing is directly related to either the coin door switch or the flippers, because I can hold both flipper buttons in-game and it works fine, and everything else works properly once a game is started.
It seems to be something that happens during the boot process/initial power-up that causes the main fuse to blow when it is powered on with the coin door closed.
I've done a diode test on the bridge rectifier in the fliptronics board, which seems fine, and replaced the ribbon cable, with no change. I had thought that replacing the ribbon cable fixed it, but it just happened to be that that was the first time that I powered it on with the coin door open.
I was going to replace the varistor, but after opening the power switch box, I found no line filter in it (which is where the I thought the varistor would be). Is there a varistor and line filter somewhere else in the machine that I haven’t found?
often times in the field a tech might come across a shorted varister and just remove it and never get back to replacing it....i suggest you put in a varister because it might save your game one day......also try disconnecting the fliptronic board and see if the fuse blowing stops......
I removed the thermistor a while back because the game was resetting right before a party, and I didn’t have a replacement at the time. I have ordered a bunch of them and am going to replace it, but don’t think that will solve my current (no pun intended) problem. The varistor could be an issue, but as I said, I can’t find where one would be in this machine. There was never a line filter or varistor in the power box by the power switch and main fuse.
The game wouldn’t boot with the fliptronics board disconnected, but I can try it again.
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