Philips 36" CRT TV shuts down with no picture

[Nick Alexander]

I have a Philips 36" widescreen 36PW9525/79R that won't power up
properly. The sounds comes on, and it seems that it is just as the
tube is being powered up, it shuts down. (There is a white flash of
raster on the screen) Then the power LED just flashes red.

I opened it up, blew all the dust out, and got it to power up properly
once with picture and sound, but then as soon as everything was put
back together, it failed again.

I realise from reading various other posts that this could be any
number of things, but I have also seen how in at least on case, the
experts were ablt to predict what the fault was.

Can anyone help? I can't really afford another TV just at present ...

 

[Jerry G.]

It is obviously a component that is failing. The answer is not simple, but
your set is serviceable.

The problem may be in the power supply or one of the scan amplifier
sections. The set is probably going in to protect.

Most of the time, these types of faults are from failed capacitors. It would
be more rare, but there may be other types of failures as well.

To troubleshoot a TV set, at the very minimum to do a reliable and safe job,
you would require to have a background in electronics, experience at TV
service, and the tools and service information to work on the set.

I would suggest to take the set to a service centre and have an estimate
done for the work. This way, the set can be properly and safely serviced.

--

Jerry G.
======


I have a Philips 36" widescreen 36PW9525/79R that won't power up
properly. The sounds comes on, and it seems that it is just as the
tube is being powered up, it shuts down. (There is a white flash of
raster on the screen) Then the power LED just flashes red.

I opened it up, blew all the dust out, and got it to power up properly
once with picture and sound, but then as soon as everything was put
back together, it failed again.

I realise from reading various other posts that this could be any
number of things, but I have also seen how in at least on case, the
experts were ablt to predict what the fault was.

Can anyone help? I can't really afford another TV just at present ...

 

[Nick Alexander]

It is obviously a component that is failing. The answer is not simple, but
your set is serviceable.

The problem may be in the power supply or one of the scan amplifier
sections. The set is probably going in to protect.

Most of the time, these types of faults are from failed capacitors. It would
be more rare, but there may be other types of failures as well.

To troubleshoot a TV set, at the very minimum to do a reliable and safe job,
you would require to have a background in electronics, experience at TV
service, and the tools and service information to work on the set.

I would suggest to take the set to a service centre and have an estimate
done for the work. This way, the set can be properly and safely serviced.

--

Jerry G.
======


I have a Philips 36" widescreen 36PW9525/79R that won't power up
properly.   The sounds comes on, and it seems that it is just as the
tube is being powered up, it shuts down.  (There is a white flash of
raster on the screen)   Then the power LED just flashes red.

I opened it up, blew all the dust out, and got it to power up properly
once with picture and sound, but then as soon as everything was put
back together, it failed again.

I realise from reading various other posts that this could be any
number of things, but I have also seen how in at least on case, the
experts were ablt to predict what the fault was.

Can anyone help?   I can't really afford another TV just at present ...

Hi Jerry,

Thanks for that. I used to repair computer monitors long ago, so I
still have some equipment. (oscilloscope, DMM) Any more pointers with
regards to the capacitors in the scan amplifiers would be much
appreciated.

 

[Bob Urz]

Hi Jerry,

Thanks for that. I used to repair computer monitors long ago, so I
still have some equipment. (oscilloscope, DMM) Any more pointers with
regards to the capacitors in the scan amplifiers would be much
appreciated.

You need to pull the main board all the way out and inspect all the
solder joints for bad connections. If your lucky, you have a cold
solder joint around a device that generates heat or is in a flex area.
Get a good solder pencil or station and redo any connections that
are suspicious.

If it worked when you had it partially apart, this may explain that.


Otherwise, its going into shutdown and that's a whole can or worms to
diagnose.

Bob

 

[Mark D. Zacharias]

I have a Philips 36" widescreen 36PW9525/79R that won't power up
properly. The sounds comes on, and it seems that it is just as the
tube is being powered up, it shuts down. (There is a white flash of
raster on the screen) Then the power LED just flashes red.

I opened it up, blew all the dust out, and got it to power up properly
once with picture and sound, but then as soon as everything was put
back together, it failed again.

I realise from reading various other posts that this could be any
number of things, but I have also seen how in at least on case, the
experts were ablt to predict what the fault was.

Can anyone help? I can't really afford another TV just at present ...

Goes white and shuts down - sounds like the 200 volt line is down to me...

Mark Z.

 

[James Sweet]

Hi Jerry,

Thanks for that. I used to repair computer monitors long ago, so I
still have some equipment. (oscilloscope, DMM) Any more pointers with
regards to the capacitors in the scan amplifiers would be much
appreciated.

He won't give you anything but that same canned response he gives everyone.

I would first check for cracked solder joints, either visually or by poking
around with an insulated stick while the set is on.

A hair dryer and a can of freeze spray can be very useful for locating
thermally sensitive components, it's the next best thing to an ESR meter for
finding bad electrolytic capacitors.