LED TV repair

fryup

Before we proceed, has anyone reading this have any experience with repairing backlight failures on LED TVs ?

how.gareth

fryup wrote: »

Before we proceed, has anyone reading this have any experience with backlight failures with LED TVs ?

Mine was crap from new, you can visibly see the stripes of lighting behind the picture. Tv was examined twice by engineers and I was told that's just the way it is. It's an LG and I won't be buying one again

Needles73

fryup wrote: »

Before we proceed, has anyone reading this have any experience with repairing backlight failures on LED TVs ?

I've replaced them on an LG tv. What's it doing i.e. Some light, no light ?

fryup

Needles73 wrote: »

I've replaced them on an LG tv. What's it doing i.e. Some light, no light ?

ok here we go....

the TV screen went blank one day, but the sound is still on

*did the torchlight test and i can see the menu

*stripped TV back & front, checked Led lights all are fine

*replaced power board and when i switch on TV all the led lights come on for a split second and then go off...so i'm baffled

Needles73

fryup wrote: »

ok here we go....

the TV screen went blank one day, but the sound is still on

*did the torchlight test and i can see the menu

*stripped TV back & front, checked Led lights all are fine

*replaced power board and when i switch on TV all the led lights come on for a split second and then go off...so i'm baffled

That's a funny one. Most likely though you still have a bad led strip. How did you "check" led lights as ok ?

fryup

with a led backlight tester

Needles73

fryup wrote: »

with a led backlight tester

Did you power up each strip or each individual led. I haven't used an LED tester but have used a dc supply on each strip. I.e. Any chance you have a loss of continuity through led or strip?

fryup

i powered up each strip and i checked each one individually and all lit up 100%

if there was loss of continunity surely they wouldn't light up in a strip would they ?

Needles73

fryup wrote: »

i powered up each strip and i checked each one individually and all lit up 100%

if there was loss of continunity surely they wouldn't light up in a strip would they ?

Yep it's a funny one. Sounds like you have tried the right things. If the power board picks up a fault it's my understanding it just switches off supply to leds. I've always found a faulty led or strip. Did you try leaving the leds on a longer test ? Sorry I cannot be of more help.

DublinDilbert

Any thermistors or temperature sensors on or near the led strips?

fryup

well there is a thermister on the powerboard, which is situated on the back of the panel

here's the powerboard