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Anselmo

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I tried In the test menu when the sound was still on (level 10) it would go down but not up. Now
it's basically stuck at zero.

In the test menu, you can only adjust the volume via the actual buttons on the pcb or the kick harness right? Not through a joystick or button input?
 

PascalP

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Have you measured continuity on the volume up botton?
Maybe it is stuck and always has continuity and that is why it doesn’t register via kick harness?
Don’t know, but worth a shot maybe
 

Anselmo

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I tested continuity, But I just made sure the kick harness pin had continuity to the button. Not sure how to exactly test for it to see if it's stuck?
 

PascalP

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Measure on both sides of the button, should have no continuity, if you press it, it should have continuity
 

Anselmo

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Measure on both sides of the button, should have no continuity, if you press it, it should have continuity
all buttons react the same way, they have continuity on both sides whether the button is pressed or not. I guess that's the problem. Kind of weird, but hopefully new buttons fixes the issue. Ordered them already
 

PascalP

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If the test button and volume down work normally I’m pretty sure you didn’t measure correct.
Check where the buttons are soldered to the pcb, measure those points, no continuity when untouched, continuity when pressed.

Do this for volume down and test, and compare with volume up
 

Anselmo

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I was able to test the buttons, they definitely did not work.

I was able to install new buttons (first time doing some Surface soldering) and I was able to test the continuity while pressing the button. It has continuity when the button is pressed. That's good....but it still did not raise the volume.

I tried to reset the volume by holding down when powering on and still couldn't get any sound. I removed the supercap that holds the settings hoping it resets the sound all the way up, so maybe that will work...but so far no sound.

I've looked for bad traces and tried both q sound and mono output and the sound stays stuck at zero. Very very weird.
 

truxpin

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Had a cps2 with the same problem a couple of months ago you will find the pcb trace from the vol up button has corroded through near the jamma connector follow the trace from the vol up button until you find the break should be fairly easy to spot the break then patch around the break with some thin wire.
 

Anselmo

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there is no vol up trace on the actual jamma edge right? You are referring to the little colored plastic row right above the jamma edge?
 

truxpin

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no vol up trace on the jamma it is however connected to one of the pins in the kick harness connector the trace runs around quite close to the jamma connector right at the point the lip on the jamma end of the plastic case contacts the pcb dirt and moisture gets trapped at this point and rots the track through
 

Anselmo

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I Should just test for continuity from the button up button to the volume up pin on the kick harness right?
 

Anselmo

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It has continuity to pin 29. So am I correct in assuming there is no broken trace?

Also it has continuity to other pins , i'm assuming since they are grounded pins.
 

Anselmo

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Update: Removing the supercap that holds the settings made the audio reset back to Max (39) - and I can now lower the audio via the volume down button, but the volume up still does not work. I did replace both volume up and down buttons, so I can confirm the new buttons do work.

Weird thing is, I still don't have sound even with the volume all the way up. I can confirm 100% this thing had sound before I lowered the volume to zero. Now it has no volume. I checked to make sure it was set to MONO since im testing it in a non q sound cab.
 

PascalP

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Update: Removing the supercap that holds the settings made the audio reset back to Max (39) - and I can now lower the audio via the volume down button, but the volume up still does not work. I did replace both volume up and down buttons, so I can confirm the new buttons do work.

Weird thing is, I still don't have sound even with the volume all the way up. I can confirm 100% this thing had sound before I lowered the volume to zero. Now it has no volume. I checked to make sure it was set to MONO since im testing it in a non q sound cab.
Are you using the Jamma mono or RCA plugs?
If you use the RCA plugs you have to set it to stereo (nothing to do with a qsound cab)
 

Anselmo

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I've tried both and make sure I change the settings in the menu for the appropriate cab.

If the audio section is dead/not working...like a dead z80 or bad audio caps, would that prevent the A board from showing the volume value go up? Or does it let the value go up but you don't hear anything?
 

PascalP

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I would say a dead Z80 would give no audio at all, regardless if it is Jamma Mono or RCA stereo.
But strange that it did work before like you mention?

And I wouldn’t recommend replacing the Z80 without troubleshooting it first, but I wouldn’t be able to tell you how.
Sure lots of folks here are able to :)
 

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I had this issue with one of my old asia boards. Try holding the down volume on the board while turning on the cabinet. Once the boot screen appears you can let go. Then try and adjust the volume.

I've also had to go into the sound test menu and lowered the volume all the way to zero. Then it would allow me to adjust to the correct volume level.

It was super finicky even after doing all this though. Replacing the supercap seem to fix the issues I was having. Im not gonna say that this will fix your issue, but for a 3 dollar cap...it's worth a shot.
 

truxpin

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now i have had a chance to to have a close look at the rest of the volume control circuit check the pcb trace from pin 29 of the kick harness connector goes to one side of R31 ( this trace is also vulnerable to corrosion damage as it goes around the rca connectors) R31 is a 15K surface mounted resistor check this resistor then check the trace from the other side of R31 to one side of D5/D6 only 1 of these diodes will be fitted test this diode for shorts this trace then continues to the base of transistors Q1/Q3 again only one of these will be fitted test this transistor the collector of this transistor then goes to pin 5 of IC F12 (TC9185P) this ic contains the electronic volume control and could be faulty but the fault will most likely be an open circuit pcb trace or faulty component stopping the volume up control signal reaching pin 5 of the ic
 

Anselmo

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Thanks for taking hte time @truxpin!!! THat was a huge help. I've been followin the traces per your instructions. The R31 test in circuit at 14.78 - going to spend some time on it this weekend to test the rest of the circuit. Thanks again!
now i have had a chance to to have a close look at the rest of the volume control circuit check the pcb trace from pin 29 of the kick harness connector goes to one side of R31 ( this trace is also vulnerable to corrosion damage as it goes around the rca connectors) R31 is a 15K surface mounted resistor check this resistor then check the trace from the other side of R31 to one side of D5/D6 only 1 of these diodes will be fitted test this diode for shorts this trace then continues to the base of transistors Q1/Q3 again only one of these will be fitted test this transistor the collector of this transistor then goes to pin 5 of IC F12 (TC9185P) this ic contains the electronic volume control and could be faulty but the fault will most likely be an open circuit pcb trace or faulty component stopping the volume up control signal reaching pin 5 of the ic
 
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