Most likely one the two diverter coils is locked on. If it was one of the other coils it would burn the fuse in one second. Look for a shorted transistor in the special solenoid section. You don't need to remove the board for testing.
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Most likely one the two diverter coils is locked on. If it was one of the other coils it would burn the fuse in one second. Look for a shorted transistor in the special solenoid section. You don't need to remove the board for testing.
Quoted from nitrocow:When I turn the machine on I hear one big click and the fuse pops
You have a shorted transistor. Disconnect these 3 connectors in the pic below. Use a DMM to test the 22 drive transistors to find the one that is shorted.
Quoted from nitrocow:Still new to pinball repair
Do you have a DMM? Do you know how to use it?
CPU (resized).PNGQuoted from nitrocow:I do have a digital multi meter
I did notice I had to transistors touching
One was Bent over
Those two rows of transistors are to control the computer controlled lamps. You need to look at the transistors next to the red circles on the pic I posted. Place your DMM in ohms and stick the black lead under the ground braid that is stapled to the wood of the back box. Then with the power off use the red lead and test each of the 22 transistors metal tabs. Note the transistors number that has a low resistance. Let me know what you find.
Quoted from nitrocow:hopefully I did it right ?
Did you remove the 3 connectors before testing?
I colored your list, green circles are good readings.
Red circle looks bad to me. These are the diverter coils.
If you cut the blue/black and the blue/green wires off of the divertor coils and insulate with tape you should be able to replace the fuse and turn on the power with out burning the fuse.
Quoted from nitrocow:Yes fuse still blows
Well then you have a short on the purple/yellow wire. Not that easy to find. With the fuse removed and the 3 connectors removed, connect your DMM to the purple/yellow wire on one of the affected coils and black lead connected to ground. Set DMM to diode test. Your DMM will be buzzing because there is a short. Now start looking for a pinch wire or a broken wire that is touching metal or the ground braid. If the buzzing stops while moving the wires around, keep looking for the problem in that area. It can be as simple as a coil lug is touching a lamp bracket. Once the metal lamp bracket is bent away so the two aren't touching, problem solved. F-14 is very tight under the PF and things get bumped when serviced.
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