View Single Post
  #7   Report Post  
Posted to sci.electronics.repair
[email protected] prc1crap@wohcrap.rr.crapcom is offline
external usenet poster
 
Posts: 4
Default Philips 19PFL3403D/F7E: Backlights turn themselves on

I hadn't thought of that. Thanks! FWIW, the value was 10K ohm.


On Wed, 22 Aug 2012 08:08:05 +0100, "N_Cook"
wrote:

wrote in message
.. .
I appreciate the input--many thanks for taking the time to take a stab
at this problem!.

Ibelieve I've found the problem--crappy soldering on the control
button assembly PC board (Philips # 715T2911-1, also used on ILO,
Magnavox, and other brands). After re-doing the joints on this board
the TV no longer turns itself on.

However, I now have another problem...during the solder removal I
managed to lose the R016 resistor that goes with the SW016 switch for
the Menu button. I took a wild guess as to the value and now have two
Volume + buttons. Does anyone have a schematic (or one of these
boards) that could tell me the value of that resistor?



On Sat, 18 Aug 2012 12:27:19 -0700 (PDT), "hr(bob) "
wrote:

On Aug 18, 10:55 am, wrote:
I was given a Philips 19PFL3403D/F7E TV because of several problems.
The original owner had had two of these. THe original unit didn't
respond to the remote, and would turn itself on and off. She sent it
back under warranty and was given a refurbished unit. It had the same
problems so she gave it to me. Then she found an old 19" CRT set and
is using that with her AT&T U-Verse box.

I hooked the set up and turned it on. Programmed itself nicely, looked
okay. I turned it off and left it for the night. In the middle of the
night I saw a glow coming from the room where the set was. The
backlights were on but there was no pic or sound. The set wouldn't
respond to the power switch. Unplugging the set and waiting 15 minutes
or so allowed it to work normally until the next time.

I tore into the set and find that the caps on the PS board all look
and test good. I replaced them with quality caps anyway. I press the
power switch and everything comes on, but there's no pic/sound. On a
fluke I unplugged the switch assembly and that restored the pic/sound;
plugging it back in turned the set off. This was repeatable. I
resoldered all connections on the power switch board and now the set
goes on and off properly but still has the "set powers up by itself
with backlights but no pic/sound" issue.

Could this be a cap related issue on the main board, or perhaps poor
solder joints? It seems unlikely that a new set and its refurbished
replacement would have the exact same problems.

Maybe you have some sort of signals in the area that trigger the set.
Like the garage door opener problems some folks have had that live
near Navy bases.



Wire-out to a pot to bracket the value