Philips 43PUS8550 no image, backlight working

[pseudorc]

Hi,

Checking voltages at TCON
Vin 12 V ok BUT ALL OTHER VOLTAGES 0

VGL1 0
VDD
vcc19
VGH 0


when connection to Left half screen cable disconnected - then other half becomes white and voltages shows down below
VGH 27.96
VCC19 1.89
HVDD 8.31
VGL1 5V
VGL2 3.8

TCON board has been replaced with similar (bought from Ebay)

Is this LCD panel issue ? the parts showing parts no is lg 6870s-2704d


Many thanks

[Diah]

if you disconnect one ribbon between T-CON and panel.. then u have clear half white on screen.... it mean the MB didnt send full channel GPU signal.... with Philips we do downgrade the firmware with upgrade_loader-pkg firmware
BTW be sure from yours TV model No !

[pseudorc]

if you disconnect one ribbon between T-CON and panel.. then u have clear half white on screen.... it mean the MB didnt send full channel GPU signal.... with Philips we do downgrade the firmware with upgrade_loader-pkg firmware
BTW be sure from yours TV model No !

Hi, thanks for your response.
Is it not supposed to happen on the other side as well ? I mean when disconnect other ribbon keeping the left one should it not replicate the white line?

Is there any downgrade firmware how to process/instruction written up anywhere please ?

Also the TV model no should be 8555 , not sure how to change it now
Thanks

[Diah]

Also the TV model no should be 8555 , not sure how to change it now
Thanks

still wrong No...LOL

[pseudorc]

still wrong No...LOL

How about PHILIPS 43PUS8555/12 43" Smart 4K Ultra HD HDR LED TV !

[Diah]

How about PHILIPS 43PUS8555/12 43" Smart 4K Ultra HD HDR LED TV !

ok, its TPM191E 8505/8535/8545/8555 Performance Series

which it share same FW with OLED.... from years 2020, you have here in this forum thread i posted of file eed you can flash it... or downgrade with upgrade loader-pkg android 11 or 9...
usb stick need formatted FAT32 NBR mode... more info you finf´d on this link

[pseudorc]

ok, its TPM191E 8505/8535/8545/8555 Performance Series

which it share same FW with OLED.... from years 2020, you have here in this forum thread i posted of file eed you can flash it... or downgrade with upgrade loader-pkg android 11 or 9...
usb stick need formatted FAT32 NBR mode... more info you finf´d on this link

Attempted downgrading , did not work , tried blindly though keeping the drive for at least 40 min

[Diah]

some things wrong you did.... stick must in MBR mode formated FAT32,,,,, use the USB port on the side USB 2 black not blue..... at same link the side i gave it to you download another version upgrade_loader

[lotas]

If you disconnect the cable from this half and voltage appears on the t-con, it means that this half is shorting out some voltage and the t-con goes into protection, take a high-quality photo of this entire strip.

[pseudorc]

If you disconnect the cable from this half and voltage appears on the t-con, it means that this half is shorting out some voltage and the t-con goes into protection, take a high-quality photo of this entire strip.

Here are the pics

[lotas]

Disconnect the lvds cable and check the resistance at these points relative to ground (on the bar itself), it should not be low or short circuited, and also check the resistance at all ceramic capacitors on the entire bar.

[Diah]

Disconnect the lvds cable and check the resistance at these points relative to ground (on the bar itself), it should not be low or short circuited, and also check the resistance at all ceramic capacitors on the entire bar.

MAN and you OP.. you have disconnected one ribbon and got half screen white but other half no image.... what are you both doing ? why playing with panel... its IPS panel who want to work on it nead to learn first how IPS working... and this why you disconnected other ribbon and no white screen display..... its funny... really funny going on here. good luck for destroying the set.,,, this is my last.

[lotas]

MAN and you OP.. you have disconnected one ribbon and got half screen white but other half no image.... what are you both doing ? why playing with panel... its IPS panel who want to work on it nead to learn first how IPS working... and this why you disconnected other ribbon and no white screen display..... its funny... really funny going on here. good luck for destroying the set.,,, this is my last.

Why are the output voltages on the T-con blocked when the non-working half is connected? Is this a software problem?

[Diah]

Why are the output voltages on the T-con blocked when the non-working half is connected? Is this a software problem?

take look on the T-con main IC... and search after IPS how video channel delivered to gate transistor. , VIA tech are absolute different yours suspect will be in place.

[lotas]

And here IPS or VIA, if the T-con blocks the voltage when connecting the faulty side.

[Diah]

And here IPS or VIA, if the T-con blocks the voltage when connecting the faulty side.

IPS depending on MB delivery... one channel or 2 channel signal , it will bw some design till 4 P1+--P4+ & p1- to p4- at the end all MB FW first then HW

[lotas]

Hi,

Checking voltages at TCON
Vin 12 V ok BUT ALL OTHER VOLTAGES 0

VGL1 0
VDD
vcc19
VGH 0


when connection to Left half screen cable disconnected - then other half becomes white and voltages shows down below
VGH 27.96
VCC19 1.89
HVDD 8.31
VGL1 5V
VGL2 3.8

TCON board has been replaced with similar (bought from Ebay)

Is this LCD panel issue ? the parts showing parts no is lg 6870s-2704d

Voltages should not disappear (VGH, VGL,...) if the panel is working properly!

[Diah]

man VGH or VGL will not present if no signal... its not fix V.. its range of Hz freq, and current which T-CON assign them to cell gate - one channel fault at PS or MB HW cause this in case you did used replacement T-CON at IPS account

[lotas]

This is the first time I've heard this, did you come up with it yourself?
So there is no signal, but when the non-working half of the voltage is turned off, for some reason the voltage is restored.
What do you advise everyone then? To put the panel into offline mode, you just need to disconnect the LVDS cable and apply 12 V to the T-con fuse and the panel will alternate colors, so where do the voltages come from (VGH, VHL...) if there is no signal.

[pseudorc]

Disconnect the lvds cable and check the resistance at these points relative to ground (on the bar itself), it should not be low or short circuited, and also check the resistance at all ceramic capacitors on the entire bar.

Caps looks fine, however R2015 seems shorted whereas others are showing 299 Ω , and not getting any reading from D24 except the top middle one 30 Ω.