Hesston, KS
It hasn't but I have a 14 pin socket. I have a spare chip as well. Should I swap it out?
(Topic ID: 224305)
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Quoted from jag8511:11-low
12-low
13-high
8- high (I'm guessing this should be low?)
9- low
10-high
And now when I test for the lower bumper on J18 it tests high and then low when I hit the skirt. It seems like it is cutting in and out.
Update - I let the machine run in attract mode for 5 min and now I don't get a reading. So when I first turn it on, it tests fine. After the machine is on for a bit I don't get a reading at all. And don't get a reading on pin 10 at all. Sounds like U45 might be bad?
Quoted from jag8511:It hasn't but I have a 14 pin socket.
Does it look like someone has replaced it? Could there be a damaged trace? If everything looks ok then I would replace it with a socket and new chip. Then start all over with the testing.
It has never been replaced. I put the socket in and replaced U45. Now all sorts of things are messed up. I don’t get a reading on the first 3 pins on J18. Funny enough, the upper pop bumper is testing fine (which was the original problem) and now most of the lights will go off on the play field after about 5 min of the game being on. Wondering if there is a lot more wrong? And I’m just causing more problems? May need to send it in to a pro for repair at this point?
Quoted from jag8511:I don’t get a reading on the first 3 pins on J18.
Are you saying no reading on pins 1, 2 and 3? Or do you mean pins 2, 3 and 4? Pin 1 is a key ans will not have a reading.
Quoted from jag8511:now most of the lights will go off on the play field after about 5 min of the game being on.
Do you mean the CPU controlled lamps? The next time this happens you should for voltage at both sides of F-3 fuse. The fuse maybe going bad, the fuse clips maybe loose or corroded. The bridge rectifier that supplies power for the lamps maybe going bad.
Quoted from jag8511:2,3, and 4. Sorry. The first 3 specials
I got to ask if you are confident on the soldering of the socket. If so then you may have a bad chip.
Everything comes on as normal but then then only lights that stay on are the 3 lights in front of the drop targets, and some random lights on the play field. However, if I start a game everything is just fine. Maybe that is normal? It’s been awhile since I’ve had pinbot on for long periods of time. So I think we are ok...but pins 2,3,4 don’t get a reading on the probe.
Quoted from jag8511:Everything comes on as normal but then then only lights that stay on are the 3 lights in front of the drop targets, and some random lights on the play field. However, if I start a game everything is just fine. Maybe that is normal?
There is a time during attract mode that the game goes thru the instructions and turns on a off lights and gives a description on the displays of the rules. Could this be what your seeing?
Quoted from GRUMPY:There is a time during attract mode that the game goes thru the instructions and turns on a off lights and gives a description on the displays of the rules. Could this be what your seeing?
Yes. I think that is what I’m seeing.
Quoted from jag8511:Weird, now I’m getting all low readings except for pins 8 and 9 on J18
Try a new chip at U-45.
Quoted from jag8511:I think that is what I’m seeing.
If you start a game and it acts normal instantly, nothing wrong.
Quoted from jag8511:I’ll have to order another one as I used the two I had ordered
https://www.greatplainselectronics.com/proddetail.asp?prod=7402
He sells good stuff.
Quoted from jag8511:Anything else I should get while I'm going to make an order?
You have 4 pins that are basically system 11s so I would keep on hand some,
10 TIP102
10 2n4401
4 Nor chip
4 And chip
2 Nand chip
50 1n4007 diodes
2 Header pins
2 IDC connectors
An assortment of fuses
4 flipper coil sleeves
10 std coil sleeves.
An assortment of some #6,#8 and #10 nuts, washers and screws
2 EOS switches
This should cover most repairs on your older 4 pins.
GRUMPY I replaced U45 with the chip from great plains electronics and still getting the same result. On J18 with the connector off pin 2 - high , pin 3 - no reading, pin 4 - no reading, 5 pin - no reading , 6 - low, 7 - low, 8 - high, 9 - low.
Not sure what to do at this point. Seems like when I replace some parts that made it a lot worse. Would pictures of the board repair help at all?
Update: I took the board off and reflowed solder to the ic socket of U45 put the board back in and turned it on. All the special’s tested high and then would go low when the switch was activated. I let it run in attract mode for about 10 min and tested again...now its
Pin 2 - no reading
Pin 3 - high
Pin 4 - high
Pin 5 - low
Pin 6 - low
Pin 7 - low
Pin 8 - high
Pin 9 - high
I’m just not sure what is going on. If I let the machine set for 10 min or so and turn it back on it all tests good for awhile and then goes back to the above readings.
Quoted from jag8511:Pin 2 - no reading
Since it worked at start up but later went bad after warm up, can be a poor solder joint or a bad chip. You may need to look at the chip upstream U-49 as the cause of the trouble. U-49 is a buffer amplifier chip so a high in = a high out and low in =a low out. So when U-45 test bad at pin 2, then test pin 5 and 6 of U-49.
Without changing anything - now the only pin that doesn’t register correctly is pin 5 on J18 after letting it run in attract mode. Pin 5 doesn’t give a reading at all.
U49 is all high except for pin 7 which is low and pin 14 which gets no reading at all.
There is also no reading on pin 10 of U45 either.
You've reached the point where I normally throw the game on CL and say "works and plays 100%. Except the bottom pop bumper, probably just a fuse." 
Quoted from PDX_Pinball:You've reached the point where I normally throw the game on CL and say "works and plays 100%. Except the bottom pop bumper, probably just a fuse."
Lol
Quoted from jag8511:U49 is all high except for pin 7 which is low and pin 14 which gets no reading at all.
Pin 14 is 5 volt power input. You get no reading?
Quoted from jag8511:Pin 5 doesn’t give a reading at all.
Is this with or without the connector installed? The cap on the skirt switch maybe dragging down the voltage.
Quoted from PDX_Pinball:probably just a fuse.
So your the guy with all the fuse ads on CL. 
It is without J18 connector connected. It’s like U49 losses the pin 14 5 volt after the machine has been on for a couple min.
So the only thing that doesn’t test correctly now after the game has been on for a few min is the bottom bumper.
I do have a 7407 chip coming in the mail. But not sure that will do it.
That didn't make a difference. Reflowed the solder but still lost power after a few minutes.
Let me know if there are any pictures or any other info that may help. I feel like we one component away from getting this thing to work right.
Quoted from jag8511:I replaced U49 and that didn't help.
Each chip has a small green filter cap by the notch in the chip labeled "B". Try snipping off the cap for U-49 and see if that helps.
pasted_image (resized).pngSnipping off a part and removing each lead separately is much easier then trying to remove the part whole. This will save you from causing unnecessary trace damage. This is a filter cap that is connected across the power and ground for each chip on the board and if it is going bad it could be dragging down the 5 volt signal. At this point in the troubleshooting you are going to have try the less commen part failures to fix your problem.
After cutting off the cap by B - U49
J18 with the connector off after letting the machine run for 5 min or so...
1-
2- high
3- no reading
4- blinking between high and low
5- low
6- low
7- low
8- high
9- high
U49 pins
1- high
2- no reading
3- high
4- no reading
5- high
6- high
7- low
8- low
9- low
10- blinking high low
11- high
12- high
13- high
14- high
Quoted from jag8511:U49 pins14- high
So with the cap removed the power on pin 14 is stable at 5 volts?
Did you install a socket for U-49? If so then remove the chip and power on the machine and test all 14 pins again.
U49 with the chip out after the game has warmed up for 5-10 min
1- high
2- high
3- high
4- high
5- high
6- high
7- low
8- high blinking and making a weird beep
9- low
10- low - high back and forth
11- high
12- high
13- high
14- high
Quoted from jag8511:8- high blinking and making a weird beep
9- low
10- low - high back and forth
These are still issues, can you remove U-45 also and then retest at U-49 socket again.
Quoted from jag8511:10- blinking between high and low
This is a problem, now that you have U-45 and U-49 removed from the board (1J-18 disconnected) there is only 3 components left that can cause this. C-72, SR-20 and ZR-5. You have replaced SR-20 already so its most likely good. That only leaves ZR-5 and C-72 as the problem. Pick one and cut it off and retest pin 10 on U-49. This needs to be a high.
Regina, SK
Quoted from GRUMPY:This is definitely not a run of the mill problem.
Have you ever been completely stumped and didn't know where to go next?
Quoted from Dee-Bow:Sorry to interrupt.. but just wanna say it's awesome to see such helpful pinsiding!! Been following for a bit now!
I couldn't agree more! @grumpy. I've learned so much and appreciate the help. I've contemplated just sending the board in but I'm kinda determined to get this figure out. I will post the results of cutting off C-72 or ZR-5 this evening.
Glad to hear this isn't a normal thing. As I was just able to fix a couple things on a Hook machine I picked up. I'm glad they aren't all this bad!
Definitely an interesting problem. Just as a sanity check, because I've been bit by this trying to help troubleshoot something remotely. Are you sure you are correctly identifying the pins on the chip? https://electronicsclub.info/ics.htm
I'm not trying to insult your intelligence, but it's easy to mix up the pin numbering, so just want to make sure that this isn't an issue as of course it would nullify all troubleshooting to date.
Quoted from robertmee:because I've been bit by this trying to help troubleshoot something remotely
I know the feeling as it has happened a number of times to me also. It's no big deal, all part of the learning curve.
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