I recently replaced my a/c relay on the aux power driver board because it seemed to be sparking green. So I socketed it and put in a 10a 24 vdc relay. This fixed my issues and so I proceeded to use clays guides to diagnose 4 transistors as bad and I also replaced 1 because the coil was stuck on. I replaced them and put the board back in. Now the relay which was previously switching correctly is back to sparking green. I at least think it's the relay but it could be the contacts for it. Thanks.

Hmm it wasn't "sparking" when I replaced and it was workng but only after I put in the transistors did it spark. Thanks!

Okay. I looked at a relay I have lying around and I do see a green LED. However, the relay that I purchased at Fry's and currently have installed in the machine does NOT have an LED. Also, the video shows me turning the machine on and at the end, the click is me turning the machine off. Upon turning the machine on, after about a second, the relay begins sparking and seems like it would continue doing so indefinitely if I did not turn the machine off. This sort of seems like Q8 is shorted but since it was working after I swapped it and before I put the transistors in, I'm not sure. Also, Q8 and its pre-driver check good according to Clay's guides. The noise in the background I believe to be largely speaker noise which goes away after a few seconds after start up. However, the sound is confounded with the sound of at least one stuck on coil (maybe the transistor fix didn't work).My concern stems from finding the old relay case melted due to high temperature and the relay pins burnt after I observed this same sparking behavior. When I turn the machine on it begins doing normal stuff, but just with the noise of the relay sparking, not clicking. Thanks!

Okay I pull out F2A and the glow continues. I pull out F2C and it continues. I pull out F3 and it still continues. These are aux power board fuses...not sure if those are what you wanted. Here is an image of the relay that was in the machine before I replaced it (the burnt one). This shows the affected area. The same issue is occurring with the relay currently in the machine. Also, F2C is over-fused it should be 5 amp but it is 6 1/4 amp and F3 is over-fused it is a 3 amp and should be 2.5. It may be important to note that the problem stopped after I put the new relay in but came back when I put the new transistors in...Thanks!

relay.JPG

Okay pulling f4 out does stop the glow. Also, I tested the diodes on the aux power board and got something kinda strange. D45, 31, 33, 35, 37, 39, 41, 43 (all the wires corresponding to the purple wired j4 connector have resistance in both directions whereas the j5 diodes have resistance in only one direction (the way it is supposed to work as i understand it). Also, I replaced the coils and transistors for q22, q23, and q30. Thanks. Do you know what size those diodes are?

Awesome thanks. So should I replace all 8 of them?

Also, if they are bad did they fry my recently replaced transistors?

Is there any Danger in leaving the same relay in?

Okay strange turn of events. I pulled out the aux power driver board and tested the diodes again and they all test fine (I guess I should always test with the board out ... ) Not sure what this makes of your previous theory guys...thanks!

Okay it is a 10a 24 VDC (not VAC) relay. The diodes all tested fine and are oriented correctly. One diode was a 1 amp instead of a 3amp so I replaced it. I measured the voltages on the relay and what I read is on the attached picture. Thanks for all the help!

Relay_Voltage.jpg

Okay I measured the requested voltages while a game was started and they're on the picture below. Robertmee, I measured the resistance as well and from pin 4 to ground and pin 2 to ground I get open circuit for both with and without the connector plugged in.

didn't you say that you get this arcing when the relay is energized??

I'm not sure if it is energized or not while sparking. It just begins sparking about one second after I turn the game on and doesn't stop...

the relay you bought...what is the current rating of the contacts? Needs to be sufficient to withstand the amps drawn...a good indication of that is the size of F4 or F2 fuses.

Not entirely sure what you're asking here... it's a 10amp 24 VDC relay. I couldn't get an amp spec off the relay I initially pulled out so I just went with what Clay's guides said (10 amp 24 VDC). Something interesting though is that the manual labels it as a 13 amp 24 VDC relay... (see page Jokerz 42)

no worries, I charge almost $100p/hr fixing machines that put people to work, least i can do is volunteer to help fix machines that keep people from work! . Keeps me from getting beaten up

Haha well without people like you and Robertmee on pinside I probably would have put my machines in a woodchipper long ago

Relay_Voltage.jpg

Okay from the left side of the fuse holder ( the one closest to the left of the board) I measure 2 vdc and from the right side I measure 70vdc. Across the left and right side I measure 5 vdc. Thanks!

Okay sparky sorry I'm just getting back with you it has been a busy weekend. I popped a new relay in just to eliminate everything and the sparking continues. I disconnected the violet yellow wires like you said from the coils I Have been messing with (top left drop target and Bttom left locking kicker). With these unhooked the sparking stops. When I rehook either of the power wires the sparking starts once again. Thanks!

Okay I've made some progress I guess... the Bottom Left 3 Bank Drop Target wires were on the kicker coil so I swapped them. With everything except for the kicker connected, the kicker works and the relay does not spark. Next, I hooked up the Bottom right drop target correctly(which had its wires on it reversed) and both the kicker and the bottom right drop target worked and the relay did not spark. However, when I hook up either of the left side drop targets , the relay sparks...thanks!