Harley Davidson Pinball Fuse blowing

Spbeyond

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Okay guys, Just got a call from about a Harley Davidson Pinball machine blowing a solenoid related fuse. Apparently it has to do with the scoop coil. What could cause this fuse to blow, could it be a bad solenoid? He wants me to come help him out just looking for ideas.
 
So here is my list to check.

Coil Resistance
Replace Diode
And then if not fixed it would be a transistor on the driver board right?
 
To measure the resistance on the coil, you'll need to clip the diode and then measure. You may not have to measure if it is toasty. Since the fuse blew, hopefully there wasn't any damage to the driver board. I'm just a novice though. There are surely better people that can help this further as I'm still learning from them.
 
Its been a while since I checked a coil's resistance and I cant remember what im looking for. Under 4 is bad and above like 20? I cant freaking remember!
 
So here is my list to check.

Coil Resistance
Replace Diode
And then if not fixed it would be a transistor on the driver board right?

If the coil energizes when you turn on the game you can suspect the driver transistor is shorted. In this case I wouldn't expect the fuse to blow right away and the coil to lock on possibly melting and hopefully blowing the fuse at some point.

Based on what you've said it doesn't sound like a bad driver transistor. I would first take a look at the coil diode then check the coil resistance. It's also possible that a wire has come off the coil and shorted somewhere or any number of other things but I would check that first.
 
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Its been a while since I checked a coil's resistance and I cant remember what im looking for. Under 4 is bad and above like 20? I cant freaking remember!

You might be able to find the specific resistance range for your coil online but if it's shorted to the point that it's instantly blowing the fuse it will be pretty obvious (1 ohm or less).
 
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