Still trying to figure out what your observations mean....

The light should be on at all times when connected to the purple X - and you saw that...the state of the drum unit zero switches shouldn't matter.

Your result at the green X is confusing me. I think the light should only come on when the make/break switch on the reset relay changes state. That's when your test lead is effectively connected to the yellow wire through that switch. I don't know why the impulse-A and drum unit switches are affecting it, unless the voltage from the yellow wire is coming the other direction through the impulse-A switch and the 10pt D.U. open at zero switch....which it could do if your O-W wire was shorted to the yellow wire.

I think those light bulb results would make sense if you had a short from the yellow wire to the left side of the 10pt coil. That's the same O-W wire that you jumpered earlier. Is the 10 pt coil locked on the whole time you're doing these tests, or have you been using that jumper in place of the original O-W wire?

Hopefully, this machine isn't too far away from you....

Tonup69 - No problem. If it helps, I think you're close. And nice job testing with the light bulb, by the way.

We went about it the long way, but I'm pretty sure from the light bulb tests, the O-W wire is shorted to the yellow wire somewhere. The O-W wire has 2 branches (marked #1 and #2 on the snippet below), one going to the 10pt relay switch (#2), and the other going to the reset circuit (#1). Their physical junction is at the lug of the D.U. coil. When you unsoldered the O-W wire from the D.U. coil lug, there were two wires, right? Are those two wires still twisted/soldered together? If so, separate them and then we can see which of the two wires is shorted.

(Geofflove and dgAmpGuy suggested this around post #28 - sorry it took so long to get there, guys!)

Since #1 is so short, running just between the D.U. coil and D.U. switch, I'm guessing the short is more likely to be somewhere in the longer run of wire - #2.

If that's true, you can re-attach #1 separately to the coil lug, use your jumper to replace the original #2 O-W wire, and hopefully, that will solve the problem.

The original O-W wire will still be shorted to yellow, so make sure the ends don't touch the wrong thing (anything connected to BLACK) - but it will be cut out of the circuit, replaced by the jumper for now, and shouldn't cause you any problems.

Paddock circuit (resized).jpg

Well, if you can't find some O-W wire, just use what you have and make a note on the schematic for the next guy.

I'll look at my wire to if I have some Orange&White. If not, put some white tape on orange wire, or the reverse.

Good job, that’s great news. It’s always tough going from a schematic, which is a logical representation of the circuit, to the physical layout and catching errors. My guess is that the solder joint cracked at some point and the wires popped off. Then someone resoldered them assuming that they knew where they went. You’ll find that a good amount of time is spent fixing errors of previous repairs... but it’s all worth it when you get it working!

Dave

Yeah! Sorry if the path we took diagnosing was a little longer than it should have been. I wonder if there was a more efficient way we could have figured that one out..

Well, in any case, you got it done - good job spotting that wiring mix-up! Now go play the hell out of that game!

I feel like I need a cigarette and a shower after that one!

Ahh...a beautiful sight!

And that light bulb tester is one of my favorite tools when working on EM's. It'll show you lots of stuff a meter won't - the length of a pulse from a switch - the strength of the pulse (the light will be dim if contacts are not making good contact)....very useful! Just be careful when you get into a machine that uses 50V - I've almost pulled out the light bulbs a couple times when I shouldn't have.

Glad you got it sorted! Have fun with it.