question about hooking up a disconnected solenoid

msignor

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So was playing my stargate and noticed that something was just "off" and sure enough, there is a kick bumper (not sure wtf it's called yet, it's #15 on the playfield) but it was completely disconnected. looks like the wires were cut.

I have the manual, but am not really clear on what goes where..

There are 3 wires disconnected.

What would be the best place to start? I am concerned that they were disconnected for a reason as a cheap fix, is there a way to test the solenoid for a short or something prior? Is there a positive and negative (I assume no, since it's a magnet - but asking)? Worst case is a blown fuse right?

Should I try and volt out the wires to see what is what? I have a feeling this is why one of the light bulbs are not actually lighting too.

I can get some pics when I get home if needed.

Thanks!
 
1st thing, work the soloniod and make sure its not froze, check the diode, if it has one, then check the corrisponding chips on the driver board. The lines were more than likely cut for a reason. Usually it blows a fuse and ops will disconnect it so they can put the game back in play. 2 wires (same markings) go on one side of the soloniod, one on the other, if it has a diode, check one of the other coils to see which side of the diodes band the wires attach to

interesting story, when I got my BSD, the top pop bumper was disconnected. I checked it, couldnt find anything wrong with it, so I reconnected it only to find out the previous owner (op) had a problem with the kickout lane, so he disconnected the pop bumper and ran a jumper to power the drainhole kicker. When I hooked the pop bumper back up, everytime it fired the kicker threw another ball into play. Took me a while to figure that one out
 
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Starting to wonder if solenoids locking on is a chronic system 3 issue or what...

My Stargate had a dead MOSFET from a coil lock on. Replaced the mosfet, worked fine until I sold it, then the new owner tells me a day later that he burned up the coil and it killed the mosfet again, and the other sling did the same thing. Have seen other reports of issues like this with Stargate as well over the last few weeks.

What the heck is it with Gottlieb sys 3?

Don't go hooking things up willy-nilly. At best you may blow a fuse, at worst, you're gonna fry your MOSFET or more. I have a manual at home still. I may be able to give you some advice if nobody else chimes in before I get a chance to look at it. If you can get us exactly what it's labeled on the playfield that would be great. Gottlieb was awesome about labeling the under-side on Stargate. :)
 
Starting to wonder if solenoids locking on is a chronic system 3 issue or what...

My Stargate had a dead MOSFET from a coil lock on. Replaced the mosfet, worked fine until I sold it, then the new owner tells me a day later that he burned up the coil and it killed the mosfet again, and the other sling did the same thing. Have seen other reports of issues like this with Stargate as well over the last few weeks.

What the heck is it with Gottlieb sys 3?

Don't go hooking things up willy-nilly. At best you may blow a fuse, at worst, you're gonna fry your MOSFET or more. I have a manual at home still. I may be able to give you some advice if nobody else chimes in before I get a chance to look at it. If you can get us exactly what it's labeled on the playfield that would be great. Gottlieb was awesome about labeling the under-side on Stargate. :)

It's #15 on the bottom of the playfield. I will go and try to verify the coil isn't locked up first and formost.
 
Transistors will short and cause the coil to lock on. When it does that, it starts to melt the insulation on the wire that wraps around the coil. Then the coil shorts.

Depending on how long it was locked on, will determine if it's toast or not. If it were me, I would replace the transistor (or 2 ) that are related to the circuit and replace the coil. You probably can't go wrong that way.
 
Are the transistors on the PCB's in the back box? Nothing looked shorted really.. I actually noticed the solenoid wasn't even tightened down to the wood so it does look like it was replaced or at least taken out at some point in time.

How would I go about identifying which transistors and where they are located? I could just unsolder them and test with my DMM for shorts, no?
 
Doesn't really make sense to replace stuff before doing some basic and easy troubleshooting. For several reasons. Not the least of which, you might introduce a problem with something that wasn't broken in the first place, compounding your problem. Just put a voltmeter across the wires that would be going to the coil and turn the game on. If you see voltage then you know that the coil would have locked on, if it were connected. If you don't see any voltage then run the solenoid test and see if you get a voltage spike on your meter when that solenoid should be energizing in test. It can be hard to see with a digital meter but should still be obvious. An analog meter will be more obvious.

Alternatively you could do a continuity check between the metal tab of the transistor driving that coil and ground but I wouldn't consider that as reliable a test as using a voltmeter with the game turned on.

If you determine that the coil is locking on then a shorted driver transistor is the most likely cause but obviously not the only possible cause. I still wouldn't just go replacing stuff. I would probe through the pre-driver with the game on to see if anything before the driver transistor is locking on but that would require the schematic and some idea of what's going on in the circuit. An easy approach would be to desolder and test the driver transistor, as it would be the most likely cause of a coil locking on. Keep in mind that the driver transistors on Gottlieb System 3 are MOSFET (IIRC).

Are the transistors on the PCB's in the back box? Nothing looked shorted really..

You're not necessarily going to see evidence that there's a problem. Many times smoke will pour out of the driver transistor when they short but not necessarily. It's as likely that it blew the solenoid fuse and someone figured out that the coil was locking on and disconnected it. Of course, there's no reason to assume anything. Just do the troubleshooting.

How would I go about identifying which transistors and where they are located? I could just unsolder them and test with my DMM for shorts, no?

Normally I would point to the manual but you won't easily find a Stargate manual online (Gottlieb). You should be able to determine which transistor it is with a continuity check between the ground wire at the coil and the metal tabs of the driver transistors.

As far as connecting the coil goes, the positive side of the supply voltage connects to the banded side of the diode. That means it will NOT be conducting when the coil is energized.

If you have 3 wires going to the coil, more than likely one will be the ground side coming off the driver transistor and the other two will be the positive side coming right off the power supply. The positive side of the coils are daisy chained together. One of the two wires will be supply from the last coil and the other will be going to the next coil in the daisy chain. The daisy chained wires should be the same color, generally speaking.

I actually noticed the solenoid wasn't even tightened down to the wood so it does look like it was replaced or at least taken out at some point in time.

It's possible that someone removed the solenoid assembly for some other reason and cut the wires to do it. Like cleaning, broken linkage, etc... That's why it makes sense to troubleshoot the problem before replacing any parts.
 
So - It looks like the coil moves freely inside the sleeve. I was able to move it with my hand.

Didn't get a DMM on it, but will do so tonight. I'm assuming that's my next step.

I also have the manual for the machine. I just don't really have much practice or experience reading the schematics to determine what transistor works with that particular solenoid.
 
So the solenoid itself fires and is functional in the self test. From what I can tell, now the leaf switch is disconnected which actually fires the solenoid. Is there anything I need to check prior to me trying to hook up the leaf switch again? I recall hearing something about diodes?
 
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