Smart tv philips 46pfl9706m/08 video garbage

[Davi.p]

Hi everybody, i'm stuck on this tv unfortunately since many months, my skills are low and my tools are few and cheap... this tv is sold on the second hand market as faulty with no image at all and no backlight, the seller said the first fault was as for the title.. it said it has brought to 3 local official Philips repair shops and all of them claims "bad panel".. I was not convincted of the diagnose so i've bought it, the first problem was to restore to the initial fault, soon i have found a lack of many tensions on the FRC + 3D board, found a bad linear reg. named RT9025-12GSP, the 3 repair shops has mad a very bad handle of the lvds flat cable and i've found it damaged nad is probably this that has made a short circuit to the FRC.. i have cut some millimeters of the end to restore it a minimum... then i have supplied that 2,5v externally and the first fault was revealed, then i have changed the Richtek Reg. with a Semtech SC4215ASTRT with adding of a 220K R in parallel with the 220k R of the original feedback voltage divider to have correct 2,5v output. Now the main fault... when the tv is cold it powers up correctly and i'm able to see the menus and the tv for some seconds then the garbage come up (blocks, troubles and finally steady vertical bars), if i switch off and immediatly on the fine working lasts less... this summer it was very very hot in Italy so i was able to see only the PHILIPS logo splashing screen at boot. Now my first thought was that the main CPU needed resoldering and then i have tried reflow but unfortunatlely i have destroyed the chip (a boubble of tin has exploded outside the DIE's glue) and i have bought a replacement mainboard. My second thought is bad soldering on the big BGA chip on the FRC board, i don't have tried reflow since it's risky, i wait some advices, tcon main chip is QFP so.. (also tcon main voltages are good). BYE! And thanks..

[chrismurphy]

Re: Smart tv philips 46pfl9706m/08 video garbage

OK whats the issue , you brought faulty TV with stated panel fault
I suspect that the panel is faulty ,that's it
I dont think anyone can offer any advice, as you have done repairs the boards wont be salvageable , total loss sorry

[dskall]

Re: Smart tv philips 46pfl9706m/08 video garbage

Can you get pictures of the screen when it is on

[Davi.p]

Re: Smart tv philips 46pfl9706m/08 video garbage

OK i have some pictures, i can't believe that panel and boards are all faulty... at least i have to understand which one is at fault, the panel look strange to me to be faulty as i think i never seen a panel that display perfectly first seconds and then go bad..

[dskall]

Re: Smart tv philips 46pfl9706m/08 video garbage

I would say not a bad panel. Have you tried disconnecting ribbon on each side of panel? Wiggling lvds cable

[Davi.p]

Re: Smart tv philips 46pfl9706m/08 video garbage

No i don't have tried, one simple test i have forgot to do, but i've done it today, with the set cool, warm up the FRC main chip before switch it on, the result is a bit confusing, i have to redo, the heatsink was very hot, at the powerup i've seen PHILIPS logo with some garbage when in the past it never do at cool, but after this it showed perfect picture (!) then switched soon off. I've tried to warm it more just to be sure it was hot not only the heatsink (just paranoia) and at the second switch on Philips logo and any other image not displayed, so i've said "Hurra'" we have a culprit, but soon i have switched it off and on and again perfect image for many seconds before to become messed up again in approx. the same time as last days... bah. I will try to warm up also the mainboard CPU and the BGA chip near the big chip on FRC. Wiggling lvds cable doesnt show any change..

[Davi.p]

Re: Smart tv philips 46pfl9706m/08 video garbage

It's incredible i can't believe it.. i've done the warming ups, each main chip and test, after each warming i haven't noticed a greater defect on power up, image seemed to work as before, each chip was very hot but it's far from be a reflow, only 20-30 seconds with heat gun not fully warm.. right after theese tests i have upgraded SW since it carries a replacement mainboard probably coming from a different model, so upgrade from .93 version to .105 then a service menu reset and now... it never stop to display WELL!! Considering the few second lasting of before, the longer lasting it's been evidentiated during the upgrade or right few before. I have hitted main chips with screwdriver handle but no changes... WHO KNOWS??