Philips 47pfl6008s wont turn on

[JorKsX]

Hello. Got my hands on Philips 47pfl6008s/12.
Problem is that it does not turn on. Last owner said the problem came slowly.
One day did not respond to remote, had to unplug from AC and then back and it worked. next day had to disconnect 3-4 times before it turned on.
And then it went into hours of unplugging and replugging until it turned on.
When I plug AC into tv, it does not respond to "turn on" button or anything else.

After 10-15minutes the TV starts blinking red LED twice.
So it blinks twice, then waits 3 seconds, then again twice and waits....
So its in some kind of protection mode?
I myself managed to turn the TV on once. it worked about 30minutes until random "white noise" lines appeared and the TV became unresponsive. Few minutes later it turned off and no response anymore. Led blinks twice but cannot get it to turn on anymore.

I have disassembled the TV and replaced every electrolytic capacitor with same capacity but littlebit bigger voltage. So if stock cap was 24v 440uf, I replaced with 50v 440uf.
And yes... replaced all I found...
I found 3.4v on the board and 12v.
Is there 5v somewhere also? Did not found it anywhere.
from the "ribbon" cable that goes from PSU to Motherboard. there was no 5v text on the pcb if I remember correctly.

I know something about electronics and I am not afraid to disassemble it or replace SMD components.
But I have no idea what I am looking for.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

Can you post some good focused straight on pictures of the whole back of tv and one of each board?

[neilc6]

Re: Philips 47pfl6008s wont turn on

If you have standby voltage, TV not turning on is likely an issue with the main board or eeprom more specifically. With the power off, you can try freezing the eeprom with an upside down can of duster before plugging in.

[JorKsX]

Re: Philips 47pfl6008s wont turn on

Can you post some good focused straight on pictures of the whole back of tv and one of each board?

Here's few pictures I took when I was in the middle if cap replacement, so some of the caps are still original.

If you have standby voltage, TV not turning on is likely an issue with the main board or eeprom more specifically. With the power off, you can try freezing the eeprom with an upside down can of duster before plugging in.

whitch one is the eeprom chip or what I have to freeze? never heard if this technique

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

with tv unplugged from power, unhook cable from powerboard to mainboard on powerboard side, leave it off, plug power cord back into powerboard and carefully test the connector pins, report the ones with voltage, as example pin 1-stndby-3.5 volts, check/report expected voltage and the actual voltage that you get.

[JorKsX]

Re: Philips 47pfl6008s wont turn on

with tv unplugged from power, unhook cable from powerboard to mainboard on powerboard side, leave it off, plug power cord back into powerboard and carefully test the connector pins, report the ones with voltage, as example pin 1-stndby-3.5 volts, check/report expected voltage and the actual voltage that you get.

Check the attachment picture.
Here's what I found when mobo cable disconencted.
pin8=0 pin7= 0
pin10 =3.4v pin9 = 3,4
pin12= 0 pin11= 0
pin14= 0 pin13= 0
pin16= 0 pin15= 0
pin18= 0 pin17= 0
pin20= 0 pin19= 0
pin22= 0 pin21= 0
pin24= 0 pin23= 0
pin26= 0 pin25= 0
pin28= 0 pin27= 0

And with mobo cable connected I cannot measure the other row but the one I can shows 12.2v on pin 11,13,21 and 25

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

Ok, you have standby, thats good.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

i think i would try a software update next, go to philips to get it, be sure to follow the procedure exactly.

[dskall]

Re: Philips 47pfl6008s wont turn on

I found 3.4v on the board and 12v.
Is there 5v somewhere also? Did not found it anywhere.
from the "ribbon" cable that goes from PSU to Motherboard. there was no 5v text on the pcb if I remember correctly.

I know something about electronics and I am not afraid to disassemble it or replace SMD components.
But I have no idea what I am looking for.

3.4v is your standby. No 5v. When did you get your 12v?

[R_J]

Re: Philips 47pfl6008s wont turn on

The standby voltage on this board is 3.5v pin9; stb (ps-on) 3.5v pins 11,12,25,26 =12vssb
I would say the power supply is working, however the led supply may not be, check for 69.3v going to the led's

[JorKsX]

Re: Philips 47pfl6008s wont turn on

The standby voltage on this board is 3.5v pin9; stb (ps-on) 3.5v pins 11,12,25,26 =12vssb
I would say the power supply is working, however the led supply may not be, check for 69.3v going to the led's

The mobo cable was unplugged from PSU the whole night. Now I replugged it and started measuring the LED pins.
At first I saw something like 39v and also found 14v. Then after 10 secconds I found the pin that was 39v is now 59.3v.
Looked at the TV's panel from the front and to my surprise... the TV was on. I did not press any power button. There is picture in attachments.

Now im scared of turning it off
I'll be posting here when it shuts off again

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

make sure all your connections are clean and secure, i clean them with isopropyl alcohol, maybe check those key voltages while its working, then if it messes up again you have something to compare with.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

another easy way to check for a bad connection is, say it goes blank again, give the wires a wiggle the ones going to the backlights etc. to see if it comes back on or there's a voltage change.

[JorKsX]

Re: Philips 47pfl6008s wont turn on

make sure all your connections are clean and secure, i clean them with isopropyl alcohol, maybe check those key voltages while its working, then if it messes up again you have something to compare with.

Yesterday before posting here I cleaned every connector with CRC Precision Cleaner PRO that is made for electronic and contact cleaning etc...
Also i've pressed on connectors and replugged them all many times to make sure its good connection etc...
I have removed every connector and replugged them all. I've removed motherboard and psu from the tv 5 times at least while testing things.
Yesterday before sleep I just unplugged motherboard cable from psu. nothing else changed...
Wierd things...

Also there is no software updates I can find and also the TV says its up to date.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

Ok, that should eliminate a bad connection, keep an eye on the expected backlight voltage, could be a weak led or possible faulty connection there, which cant be reached easily, hopefully not tho.

[JorKsX]

Re: Philips 47pfl6008s wont turn on

Ok, that should eliminate a bad connection, keep an eye on the expected backlight voltage, could be a weak led or possible faulty connection there, which cant be reached easily, hopefully not tho.

I've fixed few backlight problem TV's and they have always turned on and worked fine... just without backlight
This one showed nothing. blinked the fault light and that was that.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

I've had them deader than dead with backlight problems.

[JorKsX]

Re: Philips 47pfl6008s wont turn on

I've had them deader than dead with backlight problems.

Good to know.
These "broken backlight" TV's are free and usually under 50€ fix.

This Philips now seems to work fine. Still powering on normally and no random white noise lines.

These kind of fixes I hate. Dont know what was wrong.
Same with cars. I have been fixing car alot and half of them are "no idea what fixed it"
Usually check engine light. read codes... clear codes and car works perfectly for years.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

Thats lucky, most of the ones i find are 90 percent broken screens, if the screen isnt broken some people are trying to get up to 100 dollars. Thats not realistic tho with new big screen ones sometimes at 300 new. Who would pay them that much for a non-working tv, not me.

[nomoresonys]

Re: Philips 47pfl6008s wont turn on

I know what you mean, I usually charge in and do a lot of different things, then you don't know what it was, in some cases if you only do one thing at a time you might find out what fixed it but I sure don't want to tear it down, do one thing put it all back just to find out you have to do it all again. Kind of like changing a timing belt and not doing the water pump and tensioner.