Comet
Williams, 1985So yesterday I noticed that my upper jet bumpet was not firing, later that night the solenoid fuse (F2) blew, replaced with a new fuse, the game worked (upper jet bumper still not working) for about 10 mins, solenoids all stopped working again. Now the main board is showing error 7 (system failure). Any idea where I should start looking? Thanks in advance for all help and advice.
A couple more notes, I was reading the manual and it says you should press the diagnostic test button to get the error code, my board always would show the error code, used to show 0, (I wish it still did). In the manual for the code 7 "occasioally the following components can contribute to this problem: U21; components in the IRQ circuit; broken leads on C9 (22 mfd) in the reset circuit; loosely seated ICs on the CPU board" I can not even locate U21, . Any help is greatly appreciated.
Quoted from cireone:solenoid fuse (f2) blew out again
Check that coil and see if it is in good shape and you can test it with a meter.
Thanks, kind of a newbie when it comes to pinball repair, what points should I be testing on the coil? Should I be doing an ohm check, dc, or ac? Sorry for the lack of knowledge, I can work on vids ok, but pinball is a totally different sport.
Quoted from cireone:Should I be doing an ohm check,
Power off the game.
Set meter to ohms,place one probe on coil lug and other probe on other coil lug,(2 lugs on coil)
a reading of 2 or more ohms should be seen anything less is not good.
1 minOkay, did the ohm check on the solenoid, checked the other jet bumper solenoids, they read about 4.4,its toast, the upper jet bumper solenoid is reading nothing, disconnected the wires from it, taped them off and turned on the machine, fuse blew within 1 min. What's next?
Quoted from cireone:fuse blew within 1 min. What's next?
Ok,Locate what Transistor that runs that coil on the board(Info and location of Transistor will be in manual).Also,Find out out what kind of Transistor that is.
Make sure that's the correct fuse that's in that F2 slot.
Quoted from cireone:Q79, and located it on the board, and the fuse I am using is the one the manual called for, 250 volt, 2.5 amp. What should I do with q 79?
Find out what kind of Transistor it is and this Pinwiki chart will tell you how to test it and Remember Power off.Trying to see if that Transistor is Bad/shorted.Click on the link below
Here it is.
NPN TO-220 package (TIP-31C, TIP-32C, TIP-41C, TIP-102, TIP-122, MJE15030, 2N6043)
Place the black lead of your DMM on the metal tab of the transistor
Probe each of the flanking legs with the red lead
.4 to .6 volts is a normal reading. Readings outside of this range indicate a failed transistor
Probe the center leg with the red lead
A "short" should be seen. If not, then the transistor has failed.
I'm a bit confused....He removed the offending coil and taped off the wire. Therefore, it's not the transistor causing the fuse to blow at this point, as even if the transistor is locked on (bad), there's no load any longer to blow the fuse. Sooooo....You've got more than one problem, amigo.
Not saying the transistor isn't bad and you should follow Mike's advice to troubleshoot, but if you have the coil removed, then you're still going to have the same problem as something else is causing your fuse to blow. Is the game blowing the fuse while sitting in attract mode or only during gameplay? When you turn on the game, you need to pay close attention to any coils activating and staying on. Lift the playfield while the game is on and carefully check each coil to see if one is getting warm/hot...If it is, you've found another coil with another bad transistor.
Were you doing anything to the game when this behavior started?
Quoted from robertmee:Is the game blowing the fuse while sitting in attract mode or only during gameplay?
The impression I got was it was happening during gameplay and the F2 fuse was blowing and he tested that coil and got no reading and said it was" Toast".I was thinking that coil was locking on and fried the Transistor....Bad diode on coil caused short?
Quoted from robertmee:Sooooo....You've got more than one problem, amigo.
Not saying the transistor isn't bad and you should follow Mike's advice to troubleshoot, but if you have the coil removed, then you're still going to have the same problem as something else is causing your fuse to blow. Is the game blowing the fuse while sitting in attract mode or only during gameplay? When you turn on the game, you need to pay close attention to any coils activating and staying on. Lift the playfield while the game is on and carefully check each coil to see if one is getting warm/hot...If it is, you've found another coil with another bad transistor.
Were you doing anything to the game when this behavior started?
I agree that I think there is more than 1 problem here. I haven't noticed any of the other coils getting hot. When I first replaced the fuse today I did a switch test and the upper jet bumper switch wasn't registering either. Could a bad switch cause this? I am thinking not, but as it is obvious that I really don't know a thing, I am thinking anything is possible.
Quoted from robertmee:Were you doing anything to the game when this behavior started?
Nothing besides checking to see if the coil was getting voltage when I would manually push the bumper down.
Quoted from pinmike:robertmee said:Is the game blowing the fuse while sitting in attract mode or only during gameplay?
The impression I got was it was happening during gameplay and the F2 fuse was blowing and he tested that coil and got no reading and said it was" Toast".I was thinking that coil was locking on and fried the Transistor....Bad diode on coil caused short?
I haven't left it on attract mode long enough to really tell you, as soon as I have started it up after replacing a fuse, I have immediately started a game.
I really appreciate the help here, I am trying to be a padawan learner here, hoping to somewhere be closer to the jedi status as you two obviously are.
Remember they're are two small coils for the coin lockout on the coin door. I had an issue w/ mine when the F2 fuse blew immediately. Checked high and low for the suspect coil under the playfield but never found anything. Lo and behold, one of those 2 on the coin door was toast! If I were you, I would desolder those two and eliminate them out of the equation - they're useless for home use....
Edit: You are using a slo-blo fuse right?
Quoted from Schusler:Remember they're are two small coils for the coin lockout on the coin door. I had an issue w/ mine when the F2 fuse blew immediately. Checked high and low for the suspect coil under the playfield but never found anything. Lo and behold, one of those 2 on the coin door was toast! If I were you, I would desolder those two and eliminate them out of the equation - they're useless for home use....
Edit: You are using a slo-blo fuse right?
Yes, I am using a slo-blo fuse. I never even thought to look at those two, which also might be a place where a wire could be grounding out, as my son stuffed a bunch of stuff in there Saturday around the same time these problems arose. I am going to have to look into this as well.
Quoted from cireone:Schusler said:
Remember they're are two small coils for the coin lockout on the coin door. I had an issue w/ mine when the F2 fuse blew immediately. Checked high and low for the suspect coil under the playfield but never found anything. Lo and behold, one of those 2 on the coin door was toast! If I were you, I would desolder those two and eliminate them out of the equation - they're useless for home use....
Edit: You are using a slo-blo fuse right?
Yes, I am using a slo-blo fuse. I never even thought to look at those two, which also might be a place where a wire could be grounding out, as my son stuffed a bunch of stuff in there Saturday around the same time these problems arose. I am going to have to look into this as well.
Worth looking into... those 2 suckers can cause a myriad of problems....
Quoted from Schusler:Worth looking into... those 2 suckers can cause a myriad of problems....
Clipped those off, got about ten mins out of it and fuse blew again. I checked out the points on the transistor and they look a little too close for my soldering skills, unfortunately I think it is time for me to throw in the towel on this one and get the help of a professional before I make matters worse. Thanks again for all the help everyone.
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