Pioneer VSX-1022-k No audio

[kerbsjacob]

Hi all,

I have a bad vsx-1022-k pioneer that I obtained with a DC protect error and no power on. After finding reset code and testing channels the Front right had DC offset and bad transistor. Replaced transistor and emitter resistors and checked most components then reset idle current. The dc protect issue was solved , but still have no audio from any channels and no audio from headphone jack . When tuner is selected and tuned to station , I can trace audio from tuner to main board, through audio select board, through connector board , to the main digital board(hdmi board ) traced audio into IC 1401 AK4588VQ codec IC. Can't find audio out anywhere. Voltages to this ic and at all regulators appears ok according to service manual specs. Can't test the oscillator to this ic because my scope is too slow. Anybody have suggestions where to go next or is anyone aware of common failure on this digital board? I have significant electronics repair experience on Tv's , and often repair boards. I want to fix the pioneer and believe issue to now be on digital board. I also have other pioneers , such as vsx-1021 with similar no audio issue(amp is fine). I isolated it to digital board, but can't locate faulty component or solder BGA...

[kerbsjacob]

Re: Pioneer VSX-1022-k No audio

Quick update, I have found the digital board and codec ic are now sending the audio back to the audio assy A board . Still trying to trace down why and where audio path stops. Does anyone know if the mute_B+ or A_MUTE signals are muted on high or low and what their exact purpose is?

[ngvuanh]

Re: Pioneer VSX-1022-k No audio

First, you need to both digital and analog inputs and tracing them down. Use a sine generator at 1 kHz so it make easier for you to work out. I only have 2 MHz portable scope but it helps me a lot.

[kerbsjacob]

Re: Pioneer VSX-1022-k No audio

Yes , I should hook up a generator, right now I have been probing around with both the scope and an earbud with a cap in series. When set to tuner and tune in a station,I have audio making it from the tuner to the audio switching board, then into digital HDMI board into the codec chip, which then sends the audio back out to the audio switching board on the proper channels. Something is stopping the audio from then making it back through the switching ic to the amplifier or to headphone amplifier. I attempted disconnecting the mute circuitry by removing the 0 ohm resistor jumper that drives the transistors that short the Audio for mute function. Very difficult to work on without a test fixture jig. Can't reach the board to trace signals easily while it is hooked up. I'm down to 3 conclusions, either the microprocessor is muting audio do some unknown reason, or there is a a fault on audio switching board or it is not being controlled properly by the microprocessor. So close yet so far away .... Spent way too many hours on this, but I'm too stubborn to give up!

[CapLeaker]

Re: Pioneer VSX-1022-k No audio

If you are getting no audio out on the analog pins on the AK4588VQ, I would replace it.

[infrag]

Re: Pioneer VSX-1022-k No audio

Yes , I should hook up a generator, right now I have been probing around with both the scope and an earbud with a cap in series. When set to tuner and tune in a station,I have audio making it from the tuner to the audio switching board, then into digital HDMI board into the codec chip, which then sends the audio back out to the audio switching board on the proper channels. Something is stopping the audio from then making it back through the switching ic to the amplifier or to headphone amplifier. I attempted disconnecting the mute circuitry by removing the 0 ohm resistor jumper that drives the transistors that short the Audio for mute function. Very difficult to work on without a test fixture jig. Can't reach the board to trace signals easily while it is hooked up. I'm down to 3 conclusions, either the microprocessor is muting audio do some unknown reason, or there is a a fault on audio switching board or it is not being controlled properly by the microprocessor. So close yet so far away .... Spent way too many hours on this, but I'm too stubborn to give up!

Sorry to drag up an old post but did you ever solve the no audio issue with this amp or the other one you mentioned? I also have a very similar model with a very similar problem :|