Pioneer VSX-1120k non working preouts

[HemiRick]

Hello everyone,

I have a Pioneer VSX-1120K that the subwoofer and and the Front R preout right next to it do not work, no signal. The amp itself otherwise works fine. I'm trying to take it apart to find and repair the bad connections to the preouts....But this thing is complicated. I need some help taking it apart. I need a manual that actually matches. I've found a manual for a vsx-60 which is very similar, but it has ribbon cables where mine has PCB's for connectors to the main HDMI board on the top. Any advice on getting the HDMI board out to get to the preouts? And the required repairs?

Thanks
Rick

[Longbow]

Re: Pioneer VSX-1120k non working preouts

Are you kidding? This thing will tell you what's wrong by running the internal diagnostics AND it will order any necessary parts automatically. I would get real familiar with the remote, the menu system and the network connections. First things first. Do a factory reset on it, then update the software. Then evaluate the operation.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Nope not kidding, have read on other forums where the subwoofer preouts fail on these if tweaked too hard, at least 4 instances. The amp works 100% fine except these 2 preouts are dead. This is not something software related, I'm very sure. Why would the Front L preout work and not the Front R?

I've found a manual to 1121k, much more similar model, almost identical.
I've gotten the top digital/computer board out and am working lower.....to the preouts.
The actual diagnosis and fix should be easy once I get there.

This amp according what pioneer says does not have a user up-gradable firmware..It is the last model before this feature became available..but I know this is not true but I need a legitimate source for updated firmware if it exists. I have no idea where to find...Years ago I found a ver 109 firmware but the info w it said it didnt fix any signmificant issues and was not essential if your amp was working fine to leave it alone.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

I got it apart Now to diagnose it. In the morning or tomm sometime....too late tonight.

[Longbow]

Re: Pioneer VSX-1120k non working preouts

Nope not kidding, have read on other forums where the subwoofer preouts fail on these if tweaked too hard

As we know, anything is possible. But it is almost unheard of to damage a line level output by turning up the volume.

This is not something software related, I'm very sure. Why would the Front L preout work and not the Front R?

Why are you very sure? Units can fail in any way they like. In fact these home theater units are even more likely to present odd illogical troubles. Due to the complexity of these monsters it only makes sense to confirm that you have updated the softwarde, done a reset and checked any on-board diagnostics. Going directly to the setup menus can instantly tell you if someone has disabled those outputs.

The actual diagnosis and fix should be easy once I get there.

A good positive approach never hurts. Please let us know your method of troubleshooting the DSP.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

By tweaked too hard I mean physically pulled or pushed on, I've read they mechanically break somehow.

Because the software does not even have the ability to turn off/on the front preouts, to my knowledge......yes I agree it does control the SW output.....

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

My quick initial tests indicate that the RCA preout connectors connect to the PCB just fine.....maybe this some weird software issue requiring a reset. I'll do some more brief test reassemble and reset.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Put it back together and know I get a blinking MACC error and the display says Amp err I know this means DC on the speaker outputs....How I did most likely screw up putting it back together to cause this? The only things connected on the back are some HDMI connections and the Front preouts and of course the power cord. I took the rear panel off and the HDMI board loose from the hard connectors and flipped it forward, out of the way. Then the 2 boards below the HDMI board stayd together as I was able to get to the RCA connections at this point. It seemed to go back back together fairly easily, but obviously I screwed the pooch somewhere.

Thanks again
Rick

[ngvuanh]

Re: Pioneer VSX-1120k non working preouts

Service manual tells you error codes or indicators.
Make sure you have 2 big cables plugged to AMP board. You don't need other small one since they are SPK outputs.
If you have oscilloscope, you may be able to find where signal stops by tracing it from inputs to preouts with help of service manual.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

I have not been able to find a service man for this exact amp. I one for 1020K and 1121K...The 1121K is closest. No ocilliscope...

I didn't touch the amp board....I just removed the top HDMI board and the back panel and then flipped the 2 boards under the HDMI forward.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Someone please help, How do I begin to diagnose this blinking MACC light?
Thank you
Rick

[ngvuanh]

Re: Pioneer VSX-1120k non working preouts

MCACC light flashing indicates failure form AMP board. Make sure you have all cables plugged, at least one ground point of each board is connected to chassis. Check power transistors to make sure no short CE pins.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Took it apart again....Amp board only has 3 connections 2 of them I didnt touch, the one I did is a PCB connector with plugs on either end; its labeled the AWX connector. The end I unplugged, plugs into the HDMI board. I inspected its pins and they are a straight and fine. The other 2 connections to the amp board I didnt touch are a ribbon cable and the power cable from the transfoprmer. The ribbon cable goes to the audio board. The optical in board and connector/Audio board below it were only flipped forward so I could access the RCA connectors on the bottom of the audio board. The ribbon cable has been inspected and is still plugged.

All cables and PCB connectors were/are connected, and yes when testing I made sure back panel was on w screws in the req'd locations for ground. So In short I've taken it apart again and found no obvious cause for the blinking MACC light......Where to go from here?

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Attached are a few pics: the 1st shows 2 of the cables going to the amp section. The white ribbon in the center. Just to the left of it under the grey cable , there's a diagonal plug from the transformer for power.

The 2nd shows the HDMI top board plugged in. The top board on the left side is the one that goes to the amp board and is the AWX connector.

The 3rd shows the Amp ribbon cable and the back of the PCB connector boards.

The 4th is the AWX connector board before the other boards were reinstalled.

[ngvuanh]

Re: Pioneer VSX-1120k non working preouts

It looks like there is pre-amp board (vertical brown board).
You can try to check that board also.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Looked over the preamp board and saw nothing unusual....Put it back together

And the minute it sees power the MACC light starts blinking......Please help someone

I have DMM and know how to use it....I cant afford to spend $400 to replace this unit.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

Thanks for the non help...

Holding down the tune- button and the multizone on/off button simultaneously for 2 secs reset the unit and now it appears to function again. I have not tested the preouts yet....but at least it now turns on and off and has a normal display.

[ngvuanh]

Re: Pioneer VSX-1120k non working preouts

Thanks for the non help...

We are here trying to help as much as we can.
It is good to know you figured out MCACC blinking issue. Good luck to the rest.

[HemiRick]

Re: Pioneer VSX-1120k non working preouts

While it comes on and appears to work it only puts out sound from analog sources in pure direct mode. Any ideas?

[budwich]

Re: Pioneer VSX-1120k non working preouts

the reset might have wiped out all assignments so you need to re-assign stuff.