Pioneer VSX-1022-K won't turn on

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

I had a couple of minutes, to check on those two regulators and they seem fishy.
They receive 10.34V, but nothing comes out from them. I assume they are bad, right.
I haven't had time yet to trace the standby relay signal yet.

Those regulators have enable pins to turn them on. You have to first check to see it they are being told to turn on briefly.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

Not much is going on, but a slight change I can see at IC103 pin #1. From 0.001V goes to 0.002V. Nothing changes at IC101.
I have checked at the CPU's standby relay output(#37) and there is the same story, except that from 0.004V goes to 0.006V when I press the on button.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

Im running out of ideas. Check pin 85 Protection1. It should be 3.3v.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

pins 34 and 71 are for protection also and are normally 3.3v.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

I will check those points when I get home.
First, I will check pin#16 for 3.3V supply voltage, to make sure that it's getting that.
I'm just wondering, if the CPU is bad, I can just replace it with another CPU found at Digikey?
I have found the whole CPU ASSY board for around $69 in case that I will have to replace it.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

Its actually a microcontroller and seems to be available. It would need to be programmed for it to work. not easily done.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

I haven't had time to check those voltages, but I have watched a video on Youtube with Dave(EEVblog) and he was repairing a Yamaha receiver.
The symptoms, were exactly as mine and with some other's help they figured it out to be a capacitor(223k) at the 120V.
My standby it looks different and I don't see a capacitor like in that receiver, but I'm just wondering, it couldn't be maybe in another place, another capacitor causing this issue?

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

In the same video, he tried to force to turn on the receiver, by adding a resistor to the base of the transistor from the standby voltage, in the standby circuitry.
The receiver did not turn on, but I'm wondering if we couldn't try the same thing?
Maybe it will give us some clue, about what is wrong with it.
What do you think?

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

In the same video, he tried to force to turn on the receiver, by adding a resistor to the base of the transistor from the standby voltage, in the standby circuitry.
The receiver did not turn on, but I'm wondering if we couldn't try the same thing?
Maybe it will give us some clue, about what is wrong with it.
What do you think?

You can try that as a last resort. If the micro does not intend the mains transformer to be powered, I would expect the display to be off and buttons unresponsive anyways.
Its best to check those other voltages any any others that may be relevant.
Sometimes I wish the manual would have a list of necessary conditions for turn on.
I could be missing something. The "power" fault finding charts seem to not care if the receiver will turn on or not.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

Pin #85 has 3.297V, pin #34 has 3.297V and pin #71 has 3.297V.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

Pin 19 should be 3.3v also. On IC203.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

I will check that voltage tomorrow.
Thank you for you help, I really appreciate it.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

At pin #19 I have 2.74V.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

At pin #19 I have 2.74V.

Thats a bit sus'. Can you scope it?

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

How should it look like. I'm a beginner with the scope.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

How should it look like. I'm a beginner with the scope.

I would expect it to be flatline DC 3.3v. Ill check the manual again.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

I took a closer look. That point is loaded by some resistors in the reset circuit.
The voltage calculates to 2.8v which is close enough to what you measured.

Another possibility is a corrupted EEPROM. Try waking the receiver while pin 5 of IC204(24C16) is shorted to ground.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

I have tried it, but did not change anything. Good idea though.

[rievax_60]

Re: Pioneer VSX-1022-K won't turn on

All three Key lines should be 3.3v while no buttons are being pressed, pins 90,91,92.

[tibimakai]

Re: Pioneer VSX-1022-K won't turn on

I will check those. It's to late now.
I was wondering, we are getting the push button signal at the CPU? Maybe we should check that to be sure.