NEED Schem. for Pioneer VSX-4900S

[Sparkey]

Hello there;

I was replacing the spkr relay in my Pioneer VSX-4900S and it worked
for a moment but the main board was not mounted yet and it moved
enough for one of the temp compensating transistors to touch ground
and it popped something. Now, the receiver in in protection and the
relay won't even fire.

I checked all the B+ and B- and they're all there. Check resistors,
diodes and transistors. Can't find anything bad so far.

I'm hoping some kind soul has a schematic for this model.
Thanks,

Spark

[Mark Zacharias]

"Sparkey" > wrote in message
...
> Hello there;
>
> I was replacing the spkr relay in my Pioneer VSX-4900S and it worked
> for a moment but the main board was not mounted yet and it moved
> enough for one of the temp compensating transistors to touch ground
> and it popped something. Now, the receiver in in protection and the
> relay won't even fire.
>
> I checked all the B+ and B- and they're all there. Check resistors,
> diodes and transistors. Can't find anything bad so far.
>
> I'm hoping some kind soul has a schematic for this model.
> Thanks,
>
> Spark



This model is too old for a PDF schematic, except for probably an
aftermarket seller of scanned service manuals, like Justmanuals,
servicemanuals.net, and the like.

Most likely you have a blown channel. Shorted output transistors, open
emitter resistor, bias transistor bad, probably a couple or more resistors
bad as well.


Mark Z.

[Rick[_7_]]

On Apr 16, 9:24 pm, "Mark Zacharias" >
wrote:
> "Sparkey" > wrote in message
>
> ...
>
> > Hello there;
>
> > I was replacing the spkr relay in my Pioneer VSX-4900S and it worked
> > for a moment but the main board was not mounted yet and it moved
> > enough for one of the temp compensating transistors to touch ground
> > and it popped something. Now, the receiver in in protection and the
> > relay won't even fire.
>
> > I checked all the B+ and B- and they're all there. Check resistors,
> > diodes and transistors. Can't find anything bad so far.
>
> > I'm hoping some kind soul has a schematic for this model.
> > Thanks,
>
> > Spark
>
> This model is too old for a PDF schematic, except for probably an
> aftermarket seller of scanned service manuals, like Justmanuals,
> servicemanuals.net, and the like.
>
> Most likely you have a blown channel. Shorted output transistors, open
> emitter resistor, bias transistor bad, probably a couple or more resistors
> bad as well.
>
> Mark Z.

Thanks Mark, but I have checked all of the above including just about
every resistor on that board.

My fear is that I destroyed an ic somewhere on another board where
signal and protect routing goes through and returns. I don't want this
to be a nightmare.

Spark

[Mark Zacharias]

"Rick" > wrote in message
...
> On Apr 16, 9:24 pm, "Mark Zacharias" >
> wrote:
>> "Sparkey" > wrote in message
>>
>> ...
>>
>> > Hello there;
>>
>> > I was replacing the spkr relay in my Pioneer VSX-4900S and it worked
>> > for a moment but the main board was not mounted yet and it moved
>> > enough for one of the temp compensating transistors to touch ground
>> > and it popped something. Now, the receiver in in protection and the
>> > relay won't even fire.
>>
>> > I checked all the B+ and B- and they're all there. Check resistors,
>> > diodes and transistors. Can't find anything bad so far.
>>
>> > I'm hoping some kind soul has a schematic for this model.
>> > Thanks,
>>
>> > Spark
>>
>> This model is too old for a PDF schematic, except for probably an
>> aftermarket seller of scanned service manuals, like Justmanuals,
>> servicemanuals.net, and the like.
>>
>> Most likely you have a blown channel. Shorted output transistors, open
>> emitter resistor, bias transistor bad, probably a couple or more
>> resistors
>> bad as well.
>>
>> Mark Z.
>
> Thanks Mark, but I have checked all of the above including just about
> every resistor on that board.
>
> My fear is that I destroyed an ic somewhere on another board where
> signal and protect routing goes through and returns. I don't want this
> to be a nightmare.
>
> Spark



I took some pics of the schematics and emailed them to the address shown
above.

Hope this helps.

Mark Z.

[Rick[_7_]]

On Apr 18, 5:20 pm, "Mark Zacharias" >
wrote:
> "Rick" > wrote in message
>
> ...
>
>
>
> > On Apr 16, 9:24 pm, "Mark Zacharias" >
> > wrote:
> >> "Sparkey" > wrote in message
>
> ...
>
> >> > Hello there;
>
> >> > I was replacing the spkr relay in my Pioneer VSX-4900S and it worked
> >> > for a moment but the main board was not mounted yet and it moved
> >> > enough for one of the temp compensating transistors to touch ground
> >> > and it popped something. Now, the receiver in in protection and the
> >> > relay won't even fire.
>
> >> > I checked all the B+ and B- and they're all there. Check resistors,
> >> > diodes and transistors. Can't find anything bad so far.
>
> >> > I'm hoping some kind soul has a schematic for this model.
> >> > Thanks,
>
> >> > Spark
>
> >> This model is too old for a PDF schematic, except for probably an
> >> aftermarket seller of scanned service manuals, like Justmanuals,
> >> servicemanuals.net, and the like.
>
> >> Most likely you have a blown channel. Shorted output transistors, open
> >> emitter resistor, bias transistor bad, probably a couple or more
> >> resistors
> >> bad as well.
>
> >> Mark Z.
>
> > Thanks Mark, but I have checked all of the above including just about
> > every resistor on that board.
>
> > My fear is that I destroyed an ic somewhere on another board where
> > signal and protect routing goes through and returns. I don't want this
> > to be a nightmare.
>
> > Spark
>
> I took some pics of the schematics and emailed them to the address shown
> above.
>
> Hope this helps.
>
> Mark Z.

Mark,,,,,

Got it! .....thank you very much my friend.
This will make my life a lot easier..

Spark

[Mark Zacharias]

"Rick" > wrote in message
...
> On Apr 18, 5:20 pm, "Mark Zacharias" >
> wrote:
>> "Rick" > wrote in message
>>
>> ...
>>
>>
>>
>> > On Apr 16, 9:24 pm, "Mark Zacharias" >
>> > wrote:
>> >> "Sparkey" > wrote in message
>>
>> ...
>>
>> >> > Hello there;
>>
>> >> > I was replacing the spkr relay in my Pioneer VSX-4900S and it
>> >> > worked
>> >> > for a moment but the main board was not mounted yet and it moved
>> >> > enough for one of the temp compensating transistors to touch ground
>> >> > and it popped something. Now, the receiver in in protection and the
>> >> > relay won't even fire.
>>
>> >> > I checked all the B+ and B- and they're all there. Check resistors,
>> >> > diodes and transistors. Can't find anything bad so far.
>>
>> >> > I'm hoping some kind soul has a schematic for this model.
>> >> > Thanks,
>>
>> >> > Spark
>>
>> >> This model is too old for a PDF schematic, except for probably an
>> >> aftermarket seller of scanned service manuals, like Justmanuals,
>> >> servicemanuals.net, and the like.
>>
>> >> Most likely you have a blown channel. Shorted output transistors, open
>> >> emitter resistor, bias transistor bad, probably a couple or more
>> >> resistors
>> >> bad as well.
>>
>> >> Mark Z.
>>
>> > Thanks Mark, but I have checked all of the above including just about
>> > every resistor on that board.
>>
>> > My fear is that I destroyed an ic somewhere on another board where
>> > signal and protect routing goes through and returns. I don't want this
>> > to be a nightmare.
>>
>> > Spark
>>
>> I took some pics of the schematics and emailed them to the address shown
>> above.
>>
>> Hope this helps.
>>
>> Mark Z.
>
> Mark,,,,,
>
> Got it! .....thank you very much my friend.
> This will make my life a lot easier..
>
> Spark



Let us know how it turns out!

Mark Z.