Hisense 65" led is blinking

[nomoresonys]

Re: Hisense 65" led is blinking

If I recall those particular fixes have to do with the jumper was not suppose to be there, you can usually tell by the board, right by or under the jumper the jumper marking will be cut in half, which means the jumper isn't suppose to be there in this application.

CORRECTION, took a quick look at the video, it is NOT the one I thought it was.

[nomoresonys]

Re: Hisense 65" led is blinking

I have the LN46C630 model with same flickering problem occuring just
after warranty expired. technician fixed it by cutting one "jumper"
(metal wire about 1/2 inch long) located on the power supply circuit
board. takes 5 minutes to fix. technician said samsung issued service
bulletin that told repair techs how to fix it. you can do it yourself
with a screwdriver, small wirecutters. i could send a photo if you wantok, not sure how to post the photo here, but here's what the technician did for $150...unscrew 17 screws, remove the back cover to the TVfind
the power supply circuit board, that's the one your TV's power cord
plugs into. On the power supply circuit board, upper left corner, to
the right of and below the large 46", there is a metal jumper labelled
JP852 that is no more than 2 cm in length. it connects something
labelled 'Input rating' and another labeled 'COLD'. the technician used
wire cutters and cut the JP852 jumper. that solved my flickering
issue, TV works great now. tech said that every size TV in this class
of samsung has the same design flaw and can be fixed like this. good
luck. i would post a photo, but can't figure it out."</i>

source: http://www.amazon.com/review/R1PD14X..._res_rtr_alt_4

It works. I can hardly believe it, but my TV went from a complete black screen after a few minutes of flickering, to good as new with the clip of a tiny wire!!! It took ~ 15mins to complete. I thought for sure it was one of those "too good to be true" moments, but since I was assuming I wouldn't get warranty support, I figured why not. When has the internet last led me astray...? Ok, we won't talk about that Happy

Samsung_HD_Tech, any chance you could inquire within and let us know what this does? The post says there was a service bulletin. If so, they know about it.

This seems like a solution for a lot of people who are out of warranty or don't want to deal with the hassle of service even if under warranty. (Read this at a few places Seems like they did put out a service bulletin, so the question is, was it a jumper that wasn't suppose to be there OR just a quick temporary fix that Samsung came up with so they didn't have to fix millions of tvs properly or give refunds? It doesn't seem that EVEN Samsung would authorize their service men to do a dangerous procedure.) my comment is at the end in brackets the rest is quoted.

[nomoresonys]

Re: Hisense 65" led is blinking

CORRECTION, took a quick look at the video, it is NOT the one I thought it was.

.

[nomoresonys]

Re: Hisense 65" led is blinking

Did also make me wonder why the tv would work for years then act up, appears to be a resistor problem. Here's an old thread about it: https://www.badcaps.net/forum/showthread.php?t=48158 So it looks like Samsung would do such an evil thing, no wonder their ass is being sued at every turn, SHAME on them.

[nomoresonys]

Re: Hisense 65" led is blinking

So looks like if you have screen flicker, the first test should be to see if your boosted voltage is low then go from there.

[buchman]

Re: Hisense 65" led is blinking

So looks like if you have screen flicker, the first test should be to see if your boosted voltage is low then go from there.

How do I test that voltage?

By the way, I own Hisense TV, not Samsung.

[budm]

Re: Hisense 65" led is blinking

https://www.badcaps.net/forum/attach...2&d=1566903686
You have 16 LED strings, the backlights dimming control is done via the T-CON board via little white flat cable between the T-CON board and the LED driver board, the control is done this way for the zone dimming control and also for the dynamic contrast so they can claim very high contrast ratio.
Did you try turning off dynamic contrast via user OSD? So if you turn down the backlights level the flicker just about disappear and if you turn up the backlights to 90% it gets worst?
You can check the PFC Boosted Voltage by checking the Voltage right between any one of the 3 main filter caps (82uF 450V) in the hot side, it should be around 380 ~ 400Vdc range, I doubt it has anything to do with the symptom of your TV.

[nomoresonys]

Re: Hisense 65" led is blinking

How do I test that voltage?

By the way, I own Hisense TV, not Samsung.

Right, that is definitely something to watch out for in Samsung tvs.

[buchman]

Re: Hisense 65" led is blinking

https://www.badcaps.net/forum/attach...2&d=1566903686
You have 16 LED strings, the backlights dimming control is done via the T-CON board via little white flat cable between the T-CON board and the LED driver board, the control is done this way for the zone dimming control and also for the dynamic contrast so they can claim very high contrast ratio.
Did you try turning off dynamic contrast via user OSD? So if you turn down the backlights level the flicker just about disappear and if you turn up the backlights to 90% it gets worst?
You can check the PFC Boosted Voltage by checking the Voltage right between any one of the 3 main filter caps (82uF 450V) in the hot side, it should be around 380 ~ 400Vdc range, I doubt it has anything to do with the symptom of your TV.

I have only 280Vdc.
So, what could be wrong?
Yea I know that I am lazy and only now I checked that voltage.

[budm]

Re: Hisense 65" led is blinking

I have only 280Vdc.
So, what could be wrong?
Yea I know that I am lazy and only now I checked that voltage.

So you are getting only 280Vdc when measure it between the two legs of those three 450vdc main filter caps when TV is turned on? Are you 100% sure? it should be at least about 325VDC when TV is in standby. Your AC line Voltage is 230VAC, correct?

[buchman]

Re: Hisense 65" led is blinking

Yes correct.

If like everyone said that it's probably the LEDs So, how do I know which one? I am assuming that if the TV lights up then all leds are working.

[buchman]

Re: Hisense 65" led is blinking

And one more thing, very strange by the way...
I have a computer connect to the TV and when everything is on and I see the desktop on the TV then I see the flickering, BUT, when I open a web browser and start watching a movie then I don't see the flickering at all.

What could be the explanation?

[budm]

Re: Hisense 65" led is blinking

Yes correct.

If like everyone said that it's probably the LEDs So, how do I know which one? I am assuming that if the TV lights up then all leds are working.

If your AC line Voltage is 230VAC then it is NOT right to have only 280Vdc on the main filter cap, are you sure the meter is OK?

[buchman]

Re: Hisense 65" led is blinking

Yes 100% sure

[nomoresonys]

Re: Hisense 65" led is blinking

Check all your diodes.

[nomoresonys]

Re: Hisense 65" led is blinking

Easy diode testing if needed: https://www.youtube.com/watch?v=nQpXBHEn09A