SHARP LC-46X20E No B/L flicker 2 sec to black

[Alastair E]

Got hold of this pretty old 1080p? Sharp set, which has obviously had a very hard life!
Poor thing is stinking--both inside and out of nicotine and crud/grime.

The main symptom was the led flashing constantly red, although once it flashed green and fired up--for a few seconds, with flickering backlight.

I could force it on by holding Source/Input and Vol down where the boot would repeat, flickering BL and then off followed quickly by return to flashing red led.

Found a pot on the BL board, so cranked it up to full....

Fired it up again into its service-mode and the backlight no longer flickered but still shut down. Second time tried, it stayed on....

I went through the service-menu and found the accumulated hours of the backlight--

30,120 odd hours.....

Hmm I think the BL tubes are pretty well worn out at that use! equates to 8 hours per day for over 10 years!

Set has also a slight tab-bond issue which disappears when warmed up, two pixel lines at far left of screen....

Picture however, considering its extreme age and hours is really very very good.

Think I'll put it aside and look for a 46" or thereabouts with cracked screen to rob the 21 backlight tubes from, and shim the tabs.....
Oh--and a Huge bucket of cleaning products!

So--Looks like they CAN make 'em to last--When they want to!

[freakaftr8]

Re: SHARP LC-46X20E No B/L flicker 2 sec to black

sounds like the backlight CCFLs are most likely burned up seen it before and cranking the pot on the back light board is most likely ramping up the current control or down the current as that failing backlights of course it's not going to work if you have one ccfl out completely it will shut down with an error as the balancing is not proper.
I noticed that sharp TVs are especially finicky with failing or worn backlights

my rule of thumb has always been that if you put a perfectly white screen on the TV look around the perimeter edges but they look brown what you're seeing is the back light tubes burned on the edges which entails a worn out back light bulb

also if you have a pinkish area of course that is a worn-out backlight failing to start up properly which will usually throw off the TV and an error code

[Alastair E]

Re: SHARP LC-46X20E No B/L flicker 2 sec to black

Ran the set white-screen, there's no huge difference at the sides to the middle, just the usual somewhat dimmer at the sides/top/bottom--This was done when the set had been on for an hour or so and was fully hot.

Obviously at 30K hours those bulbs must be pretty much done though.....

[CapLeaker]

Re: SHARP LC-46X20E No B/L flicker 2 sec to black

They are getting up there.

[finntricky]

Re: SHARP LC-46X20E No B/L flicker 2 sec to black

just picked one of these sets up, just flashing red led, go to take the back off and find it only has 5 screws in it, (alarm bells ring) looks inside, and its missing most of the screws from boards, someone has had a go at this and give up,
anyway, i have replaced the screws and pluged it back in and still the same red led flashing, so my question is, where is the best place to start with this, i do have 5v stand by, but nothink else at the moment, also tryed the vol down and input at power up and get the red flashing twice and green flashing twice, but no boot or back light at all.