Philips 32PFL5604H/12 - No backlight. Sound & video ok.

Hi,

First post here. Please be indulgent.

Five years old TV set. Backlight suddenly stopped, black screen. Can see picture with a flashlight facing the screen. Sound is ok. No burned smell.

Suspected inverter on board PLHL-T808A MPR 0.1 2722 171 00749.

Removed and measured @~23°C the transfo T701.
Primary winding: 0.4 Ω including test leads.
Secondary winding EL45-GR7: 148 Ω.
Secondary winding EL47-GR3: 114 Ω.

Tested the T701 on a function generator with 1Vpp on primary. See pictures.

Three questions:
Is this enough indications to be sure only the T701 is defective?
Should I go for a full T808A board replacement?
Is a new board 2711 171 90104 a direct replacement for 2711 171 00749?



Many thanks and happy new year.

Look at this https://www.elektroda.pl/rtvforum/topic2941809.html#14190234
It is your case

Hi,

Thanks for quick reply and link. Would you explain me how to go to "(attached) SCC_86941 "TV set cannot power up/start-up", to check transformer T701". Noob didn't find it. Found

Also on topic Felix10 found that winding resistance values were around 112Ω. Seems I've one which is way over this.

I try to keep repair cost as low as possible even if I understand that a new board will fix it but a new board is around 150€ here. So half the price of a brand new LED TV same size.

Will try to go further with this helpful forum and will report any results, bad or good.


Thanks again,

Problem solved. Replaced T701 only.
For information the TV has already been running for 18.840 hours.

Look here for more information: https://www.elektroda.pl/rtvforum/topic2941809.html#14303566 .