Hello everyone, my black knight pinball has a coil that is smoking. The coil is for the top left drop targets. Is this just a bad coil or is something else doing it ( board issue or something). The coil is really hot and it feels as if it has electric going to it. Also noticed that in the door there is also a humming. All the other coils work. Any suggestions? Thx
Would that transistor be in the power board? That is where the plug is that gives the coil electric. Or would it be in the driver or CPU board? Thx for your help
Usually you want to replace the larger coil driver transistor, and the little pre driver transistor.
Turn off game, and check the coil with a meter (if it was smoking, like Loyd said, it's probably fried).
You have to do it all at once, because a shorted transistor will fry a new coil, and a shorted coil can fry a new pair of transistors.
The transistor is on the driver board.
The manual can help you identify the correct transistor.
Or, just feel them. One will burn your finger... 
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info
Thank you for all the help. Never changed out a transistor, is it difficult? Could I cause more issues
Quoted from Viking11:Thank you for all the help. Never changed out a transistor, is it difficult? Could I cause more issues
One part? Not so tough. But, you need the right tools.
Check this out...
http://www.pinwiki.com/wiki/index.php?title=General#Desoldering_Printed_Circuit_Board_Through_Hole_Components
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info
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