The lower left pop bumper locked on and cooked. (I may have had the switch set a little too close) This of course blew the F2 fuse. So I replaced F2 and clipped the wires to the locked coil and removed it (Waiting on a replacement from Marcos) powered the game up and all the coils are firing again EXCEPT the lower right pop. Is the lower right tied to the lower left somehow? Will it start working again when I replace the coil on the lower left? thoughts...
Chances are the new coil will get locked on too, if there's a bad driver or pre-driver transistor that's bad.
When you cut the wires to the coil, did you cut 2 wires that were connected to one of the coil lugs? A lot of time the power wiring daisy-chains from one coil to the next, it's possible you cut the wire carrying the power from the bad coil to the other *now* non-working pop bumper coil.
Also put in a Special Solenoid Saver (SSS) board.
It puts a 2 Amp. fuse in line with every single Special Solenoid.
https://nvram.weebly.com/repair--conversion-kits.html
Don't forget to add fuses in line with the bridge rectifiers in the backbox.
Or add one of my Bridge Boards.
http://home.kpn.nl/p.koch3/bridge_board.htm
Available from Big Daddy Enterprises and Marco Specialties.
Yes. I cut all three wires to. The coil. Do you know where the transistors are? I can do the board work if I know what to change
It looks like the lower left pop bumper goes to Q4 (a TIP120 transistor, but replace with a more durable TIP102 instead), which also has a pre-driver 2N4401 transistor that usually should also be replaced. Is there 2 red wires and 1 red wire with a blue stripe going to the lower left pop bumper coil? I just want to make sure I'm giving you the correct info.
The 2 red wires you cut off the pop bumper--those are the power wires for that coil, and most likely the power wire for the other coil that stopped working after you cut those wires (like i said, the power daisy-chains from coil to coil).
If you splice the 2 red wires together, the other pop bumper should start working again. Don't connect the red/blue wire to anything in the meantime of, course.
Looks like the info in my above post should be accurate--Q4 and Q5 should probably be replaced. I would check those transistors with your dmm before installing the new coil (and potentially frying it if there is a bad transistor or 2).
Latest update. The transistor Q 4 actually has a bit of the black (Heat sync?) missing. Did this possibly get so hot it broke off? I am planning on ordering a new TIP and the driver. Would these make the pops completely inoperable?
Quoted from Scmitchell:Latest update. The transistor Q 4 actually has a bit of the black (Heat sync?) missing. Did this possibly get so hot it broke off? I am planning on ordering a new TIP and the driver. Would these make the pops completely inoperable?
If the transistor is cracked it's busted. Anything connected to it is not going to work correctly. That is the classic way that those TIP transistors break - pieces will blow off, or you'll see a solder-like ball on the end. The heat sink part of a TIP transistor is the metal tab. The black stuff is the transistor body itself.
Quoted from vid1900:Buy 2 dozen of those TIP102, the pre transistors and 4004 diodes.
Just about every repair on a pin is going to somehow involve those parts.
I ordered a ton of both bits and more molex connectors.
ok. I had the wires backwards on the coils and immediately popped Q4 again. Diodes were opposite of originals. I replaced Q4 AGAIn and swapped the red wires to the banded side. Now I have the right pop operable but the left one is still dead......why do I have the left out and the right working?
I replaced Q3 and Q4. Then I fried Q4 when I gave it the smoke check. I then Replaced Q4 again and I did not replace Q3 the second time. Would a predriver prevent the one pop from working on the left while allowing the other on the right to work?
A single predriver runs a single driver that goes to a single coil. Blow a coil, it starts a daisy chain back to thru the driver, predriver and the latch on the chips. Over fuse something, you can smoke the boards and get a hole thru it, and parts will drop off.
Using a jumper wire, ground one end to the backbox braid, and quickly tap the top of each of the drivers, and it will pop the coil that the driver is attached to. Easy way to test these older pinballs. Don't try it on the newer ones. This will test the wiring from the driver to the coil to make sure it will work from that point. If the coil is wired correctly, and has power, it will pop the coil. Then if the coil works, try a game, and if it doesn't pop the coil, the driver or backwards parts are bad...
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