Hello!

Need some guidance into the latest issue on my Xenon. The "middle" pop-bumper energizes the second I power on the game. Doesn't blow any fuses. If I disconnect J5 (center pop is J5 pin 15) from the driver board it does not charge. If I disconnect the coil the switch works properly in game.

A little background to this issue:

I accidently wired this pop the wrong way - power wire to the non- banded diode I turned on the game and started smelling the very unique smell of what I found later discovered to be the coil. It blew the F4 fuse on the rectifier board which I found was too high (15amp). Then it blew up the resistor/transistor on the solenoid board.

I traced the Transistor feeding the coil (Q10) and replaced it with a TIP102 along with the 330k ohm resistor and 1N4004 diode in it's circuit (pic incase I missed something important to replace?)

I replaced the Bally coil, AN-26-1200, with a spare Williams A2-26-1300, assuming they would be compatible?? I put a 1N4004 diode facing the same way as the rest of the bumpers and put the yellow power wire to the banded side. I also replaced the switch diode and clipped the cap to make sure it wasn't shorting and like I previously mentioned, the switch works in-game when I have the coil disconnected.

Any ideas what else to check?

TYVM!

SmartSelect_20220911-151111_Adobe Acrobat (resized).jpg

Would U3 need to be replaced as well? Not too familiar with how IC's flow/operate but noticed U3 in the schematic of where the transistor is for that pop.

Screenshot_20220911-163512_Adobe Acrobat (resized).jpg

I'll have to double check the resistor just to make sure. Ty for pointing it out - I seem to remember seeing "K" on the multimeter but could be mistaken. How would I go about measuring the transistor in u3?

Update: my DMM shows a "K" for these resistors even though they are only 330ohm... maybe it means something else? Not sure but it goes away when not measuring.

Thank you so much! Very useful information. I'll have to do some testing when I get back home and will report back.

Good news first - the pop works!
Weird news: read below...

I don't have a way to test a cap but I measured the ic @ U3 for Q10.

Diode test mode
Red lead to pin 8 (bottom left leg)
Black lead - pin 7 = .625
Black lead - pin 15 = .649
Measurements are in the proper range.

I re-tested the TIP102 @ Q10 and it was bad. Replaced with a TIP120. Pic of area attached - look for the different resistor/diode. The coil no longer locks @ startup!

Now the weird part...

When I'm in a game, none of the solenoid switches are activating or coils firing with the following exceptions:

The center pop that was just "fixed" , the flippers, drop target reset (switches not working though), ball kicker and the kicker that launches the ball to the shooter lane. All of these are working fine.

ALL of the other solenoids are not firing in game, however, all of them work in solenoid test mode. None of the solenoid switches are recognized in-game OR switch test mode except the ones I mentioned above. They all used to work in switch test...

I can hear something "click" off when I start a game, thinking it's related but I can't trace where it's coming from. Not a fuse and doesn't sound like a blow of any kind, more of a clicking like it's turning off these switches/coils from working at that moment. When I first started the game up the top eject saucer switch/solenoid worked then I heard that "noise" and stuff went dead. I hear it typically right before I launch the first ball now.

20220912_000827 (resized).jpg

Just wanted to conclude this last issue - there was two wire's going to the center pop's switch. One of the wire's broke. Re-soldered the two together and put it back on the switch and all solenoids now work fine. Thanks all!

This may be for another thread, but the last thing I need to look into is how the drop-targets are supposed to work. When I roll over the first roll-over button at the top, the first drop target falls but nothing is scored and the light doesn't move to the next roll-over/pressing it doesn't drop the second drop target. The rest of the roll-overs make a sound and score but don't drop targets. If I hit the drop targets with a ball there is no score and once all of them are down, they stay down until the next ball resets the bank. All top roll over switches activate in switch test, none of the drop switches activate when pressed closed but all coils fire/drop in test.

Didn't get a chance to look thoroughly yet and I might be a bit dense but which diodes are you referring to? I did see this series of caps near that connector and wasn't sure if the circled cap looks damaged?

Also included a pic of the switches. None of them activate in test mode and are the only switches not working. All contacts are separated and close properly when the target drops...

20220913_144919 (resized).jpg

20220913_161854 (resized).jpg

Are these the diodes you guys are talking about? If so it looks like the banded ends are connected?

20220913_220652 (resized).jpg

Ok, will check out the MPU board for this.

That is my doing. I was reflowing solder to some lugs and the solder iron shaft pushed into the coil sleeve when I was trying to get in the proper angle. Whoops!

Attached pic of the diodes - they appear to be in the correct orientation?

The common wire (grey/yellow circled on pic) did not have continuity. I rewired and verified continuity from the first switch on the roll-overs to the last switch on the drops.

Still doing the same thing.

I swapped the drop target 1 & 2 switch wires. Also clipped all caps on the roll-over targets and replaced the 1st switch's diode.

Hitting the 1st roll-over button in-game still does not score any points but drops the 1st coil, so this test failed. Since it didn't score it doesn't move onto the second button.

In test mode all the roll-over button's register but only the first one doesn't score in game... Strange...

20220914_172739 (resized).jpg

20220914_184210 (resized).jpg