All slingshots, (lower and upper), are not working during gameplay.

I've jumpered the switch row/column in test, and I get correct switch closure alert.
I go into solenoid test, and all four slings kick.
I short the transistor and they fire.
I ground the non-banded end of the diode and they fire.

Not exactly sure, in reading the schematics, how the switch closure fires the coils. It seems to be controlled through
the CPU, since I see no direct connection from the switches to the coil.

We're dealing with special solenoids #3, 4, 5, 6.
3 -> Q73
4 -> Q69
5 -> Q77
6 -> Q79

It seems they all work through all the tests, except they don't work in the game. If I have the game running, I can manually
move the kicker, and points will score, so the logic side is working, it just isn't firing.

I've verified through tests and with meter, that I have power at the coil.
Need a direction to try next. I'm not sure if I'm dealing with a logic issue that triggers the coil to fire during the game or what.

In test, I can hear the relay clicking on and off, so I know that is working, in case it involves that.

Doug

Ok, would I ground IJ18-5 to fire Q75 by pulsing a zero to the input of U45? I suspect if I do that, it will fire on the output (assuming this is an output), on pin IJ19-7? Want to make sure I ground the right things.

This one is tough.
I re-flowed the two input and output connectors associated with this issue.

I shorted out the input pin on each input to U45 and it didn't fire. So then I touched ground to the actual pin on the chips U45 and U50
pertaining to the input and they didn't fire. Both chips have been socketed.

I pulled the CPU board and ohmed out all the connections on both chips, and they were good. I also checked connections between the chip and the pre-driver, and the pre-driver to the TIP122 which was good.

I have been putting in 7402 chips that have different numbers too, in case that causes a problem. 74ls7402, 7402N, and now it has a Dm7402. Doesn't seem to matter.

I then found each orange wire coming from the four kickers and verified their connection back to the top input connector. All good.
This is bizarre.

Something interesting. I believe when I measured the voltage at the coils, it was 26v. Honestly, I never checked to see what the correct voltage was, since I had voltage, I just moved on. In looking at the schematic, I notice that it is coming off the power supply at 34v for the coil power. I think it was 3J3 on the power supply. Could the difference be enough to not fire the coils?

Yeah, I thought about that after I posted it. Pffft.
I'll still check on that to see if anything is wrong.

I keep going over it in my head, as I see the schematic, the input, the output....
Everything works when done through the logic side, just not the switch activation side,
so, is there a possibility of a ground being missing, if it works through the CPU activated side,
or does that show that everything is in place, if the CPU can fire it? Just trying to figure a new
tactic.

What would you say about this guy's post about pins being cracked, and coils working during test,
but not game play?

https://www.instagram.com/p/BQ_fzTmjyVa/

Ohhh!
I think I know what I did wrong!
Reading through your post, it struck me what you were trying to say. The flipper power has to be enabled, for the nand-gate to
get its input. Well, when I tested, the game was just turned on, not in a game! I'll have to go back, now that you've shined some
light on an important detail I was not aware of....or didn't read carefully enough if you mentioned it.

You're really helping more than you know. The inputs and outputs were confusing, because I couldn't figure out how the input pulse from the switch, was getting to the gates. I didn't notice the line going above all the circuitry, all the way over to the gate, and I then realized one connector was inputs, and one was outputs. Now I've learned the game being on and testing, is not the same as the game actually in a game, and relays being pulled.

Definitely some great responses. Sure appreciate the added knowledge with pictures, that allow me to think about it and follow your point.

I'll go back and test tonight, with the game on, and maybe we'll see some different behavior.

Ok, I pulled the power supply and found many cold solder joints. Got them all fixed up, but no action during play. I did however go back in, and re-test the triggering of the coils, by grounding the correct input pins, WHILE the game was in play, and they work.

So now we have it to where it will work in every aspect, except for live game play. We know the logic chips are good, from the playfield input, we now have no cold solder joints, so how does this circuit get it's ground, to complete the path?

I also mentioned that I metered out each of the orange wires, back to the input connector and they were good, from the playfield.

Seems we're close, as I've tested all around the problem.

I followed what you were saying, and when I go to my power supply, on connector 3J6 pin 14, there is no wire. I also found in the schematics, page 72 of the Fire! schematics, where you were talking about. On Fire's schematic, there is no connection on pin 14. It just stops. That correlates to my game not having a wire on pin 14.

Wayout440, where would you like me to verify the wire color at?
I can check tonight and list off all the wire colors coming off the switches if needed.

I can't post pictures, I don't think I donated enough here, but I just posted what you did, about the pin 14 being vacant.

Let me know, and I'll do more checking.

Great, I'll let you know and maybe take some pics.

Ok, you're not going to believe this, and I can't even get my mind around it, but I traced the white wire
after numerous wrong turns, to the CPU board. Connector 1J18-7. I measured from the switch under the playfield, all
the way to this connector, and it had continuity.

I yank the CPU out thinking there is a bad solder joint, broken trace, something. But it goes to a pin that connects to nothing.
The schematic even indicates NC.

I want to jump a wire over to that pin from logical ground, but this thing had to work before. I just bought it from a guy in VA,
and had it shipped. He said it had a few issues, but with the replacement of U45 and U50 and a ramp coil, everything was fine, except
for the slings.

I'm very curious what you will come back with...I'm shocked.

Special Solenoid White Ground Wire (resized).jpg

2017-04-26_213620 (resized).jpg

I was told by another guy, that a Road Kings has a wire go to the same spot as mine, then loops
through pin 6, then takes off through a wire, through a bullet connector, and over to pin 14 of 3J6 on the power supply.

Mine simply terminates 1J18-7, has no loops, has no wire and bullet connector, and has no wire on pin 14 of 3J6.

I bought this from a guy and had it shipped, knowing it had some issues. He had cut the wires on the up and down solenoids of the ramps,
and also disconnected the bell and knocker. I got everything working, with new transistors, new U45 and U50, and new ramp-down solenoid since this one was shorted. Slings are last item. Do you think I need a jumper?

Grumpy,
I have the CPU still on the bench. I'll go see if I have continuity from the pins 6 and 7 to the screw holes. I think I did that, and found
I had no connection, but I'll re-test real quick.

No connection on that entire connector to ground.

Grumpy,
The serial number sticker has 541 on the left, and on the right 92849.

As for the white wire, no, it terminates at the CPU. I would have to create a jumper, like they were talking
about, is on Road Kings, and connect it over on pin 14 of the power supply for ground. Don't know what to think
here, except the wire got removed?

There has been work on it. It looks like the bridge went nuclear at one point, so someone may have removed the wire
and never put it back....I just didn't know if I should jump over to a ground source, if it wasn't supposed to be connected
like that. But at this point, there is no ground as far as I can tell.

Well, stupid of me not posting initially that this was a recent purchase for sure. I totally agree Wayout, that
having said that in the beginning, things might have been done differently. Like you, I assumed it was a cut and dry
case of it being a working machine, as he stated, with just a couple of problems. smh....

I have to say, one learns the most, when put through troubleshooting hell, and I've been through it with
this machine! I also learned a LOT during this troubleshooting session. And as crazy as it seemed, I felt we
really needed a jumper to ground to fix it, but it still seemed crazy. Grumpy brought it all together with his sleuthing on the serial number.

I'll get this set up to have a ground wire to the power supply, since that is what it needs, and I'll report back, for
others who might follow this thread in the future.

Happy to report, all our efforts paid off!
I connected pins 6 and 7 together and connected that to the outer ground plane on the CPU. Great to see those slingshots fire!

Thanks for all the help, and for imparting some of your knowledge onto me.

Doug