Most likely, U-50, 55 or 56 is bad. Do you have a logic probe?
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If that test good this brings us back to U-50 again. The output of U-56 pin 6 is connected the the inputs of U-50 at pins 8 and 9. Both of these inputs should be low as they are tied together, And since a NOR chip is also a inverter chip the output on pin 10 should be a high. Now since your special solenoids are not working during a game but work in coil test you are not getting the low signal from U-56 pin 6. Either U-56 is bad or there is a broken trace between U-56 pin 6 and U-50 pins 8 and 9. Let me know what you find.
Quoted from grantopia:(Test mode: testing coils returns same results, no jets, kickers, or flippers.).
If the flipper were to work but not the special solenoids this would lend itself to a U-49 issue. But since he grounded the transistor tabs and the coils worked but the flippers don't, this will be a enable issue. When the game is placed in coil test the enable should be turned on and then the pia chips fire the coils. Since controlled coils are firing but not special coils the blanking signal is good but not the enable. So I'm going to stick with U-50,55 or 56 is bad.
Quoted from grantopia:And I didn't mean to imply you weren't on the right track with the suspicion,
No I didn't take it that way. That's why forums are great, a bunch of nice people trying to help others out looking for nothing in return.
Quoted from boscokid:Grumpy teaching another graduate level course in component level troubleshooting!
Maybe not!
https://www.ispot.tv/ad/7oMF/holiday-inn-express-the-solution
Quoted from Definitive:Pin 11 - no reading
Pin 12 - low
Pin 13 - low
Since this is a NOR chip you need both inputs to be low to get a high output. Pin 11 is the enable input coming from the PIA chip U-10. Did you start a game before this test? Has anyone replaced U-50 in the past? Can you check the output of U-10 pin 19 after starting a game, what do you get?
Quoted from Definitive:U10 pin 19 yields high in attract, low in game
OK somehow this low in game signal is not getting to U-50 pin 11. There must be a bad trace or poor solder joint some where.
I think it is time to pull the CPU board out and do a continuity test from the U-50 chip lead pin 11 to the via point on the bottom of the board under U-49. This will confirm if the U-50 socket and socket solder joint are good to the bottom of the board. If that's good then you will need to test the U-10 socket.
Quoted from Definitive:Without interruption?
Yes, but is not a very direct way. It will change from the top to the bottom of the board and maybe back to the top again.
I suppose this maybe a good time to ask if you are capable of this type of repair. If not you can ship it off now with a note of the problem and it would be an easy fix for a pro. If you are then post a good pic of the back of the board so everyone can what you are up against.
Quoted from Definitive:I know its not pretty, but it works, now the test results are as you described
You should be go to go.
Playball!!
Quoted from Definitive:What i do not have now is top, right or bottom jet, ball save or the solenoid where the ramp drops the ball in the left side.
Additionally I noticed the relay under the playfield (under shooter lane) pulses non stop during game mode
I'm stuck at work till midnight, will look this over when I get home.
Quoted from Definitive:What i do not have now is top, right or bottom jet
Solenoids 19,21 and 22. OK. Do they pulse in coil test?
Quoted from Definitive:ball save or the solenoid where the ramp drops the ball in the left side.
Solenoid 6 Power kicker left outlane. Do you hear a relay clicking in coil test?
Quoted from Definitive:Additionally I noticed the relay under the playfield (under shooter lane) pulses non stop during game mode
Find this relay and tell me what color stripe is on the brown wire.
pasted_image (resized).pngQuoted from Definitive:That relay has Brown with White stripe. ( this is Also the relay that pulses non stop in game mode)
Could this be a faded yellow stripe?
Quoted from Definitive:But im Headed back under the playfield now... during coil test the F2 SS fuse popped, im now showing continuity to ground on 3J3-6 Red wire, White stripe, (sheet shows vio/blu not accurate). Regardless, with connector unplugged this wire in particular shows contact to ground.
F-2 fuse is connected to pins 6,7 and 8 and should all be a red wire. Pins 4 and 5 should be a red/white wire. Was this showing ground while the game was turned on or off? If it was with the game on then disconnect 1J-19 on the CPU board, did the ground go away? If yes then replace the fuse. Does the fuse blow now?
Quoted from Definitive:I cannot help but think power from the battery tray made its way down the damaged trace to the chips on either side, (U10 pin 19 and U50 pin 11). Both had continuity to the blob when I located it.
The chips U-10 and U-50 both work with voltages from zero to five volts DC. So depending on which terminal of the battery holder making contact you had either 1.6 volts, 3.2 volts or 4.8 volts. None of these voltages would have cause any damage, but they would have caused the enable signal to stop changing from the low to high which will stop the flippers from working.
With the game turned on test for DC voltage on 1J-18 pins with the connector left on the board. Post the readings.
Quoted from Definitive:I counted wrong, pin 4 (red/white) shows ground both while on or off.
I kind of thought you counted from the wrong direction.
With J-19 still disconnected and the machine turned on measure ohms from each pin of J -19 to ground. Then start a game and retest. Report the results.
Looks good with the power off you can reconnect any loose connections. Then preform a cool test, note what's not working.
Has someone tried to install LEDs in the flashers? For 5a and 6 coils there is a relay to activate them. On the relay there is a wire on the terminal marked gnd, it's a white or black wire. Do a continuity test from the ground braid to this GND terminal on the relay.
Now you have 3 pairs of flasher bulbs not working. These are #63 bulbs and are wired in series, so if one bulb in the pair is bad then neither bulb works. Remove and test your bulbs first with a 9 volt battery and jumper wire. After you test both bulbs, place game in coil test and pause test on the correct flasher. Now take a jumper wire and bypass the dropping resistor for this pair of bulbs. If the flashers work when you install the jumper the dropping resistor is bad and needs to be replaced. The larger resistors on the resistor board are the dropping resistors.
And the last coil #16. This on the coin door. If you turn on the power. Then drop a quarter in the coin slot does it come out the coin return or does it drop into the inside of the machine?
Quoted from Definitive:Theyre red on the 1 board
This is a A/C relay and isn't the same as the other 2 snubber relays.
Quoted from Definitive:and white with red dots on the other 2 that say "snubber"
With the game power on what do you get for DC volts between the terminal marked 28 and the other terminal marked GRD?
Quoted from Definitive:No coin mechs, i just posted the results in case you needed to see the # for diagnosis purposes.
Then no need to worry about this.
Quoted from Definitive:The snubber beneath the left upper kicker pulses to the sound of the A/C relay between the 28v tab and its own ground, and shows no readable measurements
I am not following you on this, could you post a short vid.
Quoted from Definitive:The snubber beneath the power kicker reads 29vdc between the 28v tab and its own ground
With the power turned on take a jumper wire and touch one end to the GRD terminal and then briefly touch the other end to the grey/blue wire. Did the coil fire?
Quoted from Definitive:Yup, fires
If you put the game in coil test and stop on #6. Then use the logic probe and test the base of Q-19 and Q -23. What do you get?
Quoted from Definitive:Coil test mode, manual, coil 6, u19
Pin 11 is low
Pin 12 pulses, low/high
Check pin 13.
This is a AND gate, and when both inputs are high/high pulses the output should be high pulses. Your output is a low. This means that the chip is bad or the pull-up resistor is bad. You can ohm test the pull-up resistor pack by checking pin 1 to pin 2 then pin 1 to pin 3 and so on.
Quoted from Definitive:Ohm Testing sr-6 in circuit
Pin 1 to:
Pin 2 = .559
Pin 3 = .560
Pin 4 = .560
Pin 5 = .560
Pin 6 = 344.2
Pin 7 = 160.8
Pin 8 = .560
Pin 9 = .560
Pin 10= .562
Pin 7 is the resistor for the coil you are working on, it looks bad. But you now know the problem was U-19. This is how parts in circuit can sometimes test bad but still be good because they are all tied together and affect each other. So for most chips they can sink current but not supply current. So there needs to be a current source, in this case it is SR-6. The power to turn on the predriver comes through SR-6, U-19 can sink that power to turn off the predriver. In this case the output of U-19 had shorted and was stuck sinking current no matter what the inputs were doing not allowing the predriver to turn on.
The pulsing relay is the A/C relay which is trying to reset the drop target. But since the drop target is stuck in the down position it will continue to pulse. This should be fixed as soon as the drop target is raised up.
Now to fix solenoid 15. You will do it just like solenoid 6 testing, but with different part numbers. Start by finding the drive transistor number on the solenoid page. Then find the drive transistor on page 2 of the CPU diagram. Follow to the left to the predriver, and note the AND gate output pin. Lock the game on coil 15 test and probe the base of the predriver. Let me know what you find.
Quoted from Definitive:U17
Pin - 8 low
Pin- 9 low/high/low (pulsing)
Pin- 10 high
This sure looks to be the same as U-19. I think it's time for another AND chip.
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