I'm no expert but after recently playing with an led screen with a dodgy string of led's I got to see the inner workings. I was guessing that all the little layers not being correctly positioned was the cause of uneven backlight. I have seen a post about using a microfibre cloth to smooth out the inner layers. Whilst in bed this morning I noticed that my tv screen (turned of was reflecting the window frame but was not reflecting it as a rectangle more an extreme concave. This got me to thinking that inner layers may have been making contact with the screen or each other. I had tried the cloth trick to no avail. So I had a thought, I used the end off my camera blower brush (rubber sucker) to gently push and pull the screen rapidly and low and behold the backlight is so much better. Just thought it may be worth a go for anyone else with this issue.
-
-
Re: Uneven LED backlight possible fix
In the only one I ever tore down to this level (Samsung D-series) the layers were held in place around the edges with two-way adhesive tape. I would say it's completely possible that the layers could come loose under certain circumstances. -
Re: Uneven LED backlight possible fix
On LG they are held in place by little metal tabsComment
-
Problem
This is an LG edge LED lit LCD Display. The LEDs are on the bottom edge of the display. There are 2 bars (left and right) Each bar has many LEDs and a 6 pin connector. Each pin drive several LEDs thus is the highest current flow / heat junction. The weak lead free solder gradually fails with thermal expansion/contraction cycling and increases resistance. PSU will compensate up to a point, then when the current is too high, PSU just shut down the backlight causing a dark display. I have even seen one which the connector just fell off as solder points became completely detached.... -
I've repaired a TV that i found standing on the streets for the garbageman. Unfortunately, the tv got wet and there was -at least, that's what i think- some moisture behind the panel. During two weeks, it became less and less, I think the moisture is gone 99%, but i still see some residu on the sheets
It's harsh to see when looking straight to the tv, but it is visible from an angle.
Is it safe to clean these layers and if so, how do i do that? -
I got this set for very cheap, it works perfectly but the catch is that the protective coating was damaged. About 45% of the screen had a green tint, you can see exactly where the layer changed colors to a blueish tone (that actually makes everything green).
"Ok, that's probably just the anti-glare layer" - I thought. So using a microfiber cloth and automotive metal polish I was easily able to turn it into a nice mirror.
Unfortunately, the damage was beyond this layer and everything still had a horrible green tint. I initially... -
I've been working for while on this Macbook Pro LB.
On the bare board with power adapter plugged in, no green light. So far I noticed that there is no PPBUS_G3H. I removed F7040 and I measure 2,1Ohm on pin2 there. So I conclude there is a short. I went to voltage injection on that pin2: 2,2V is drawing 1,1A. I found the board is warming at C7553, c7555 and C7556, so I removed those, but still the board is drying the alcohol at that spot. There are no more components there!
Can it be that the trace in the layers of the PCB are damaged? It is an board with older water damage that... -
Hi,
I have a Macbook Pro 13" 2019 A2159 on my desk with what seem to be SMC issues.
Powers on by itself, fan on max all the time, touchbar black. Everything else works as it should.
While examining it's clear repairs have been attempted before.
So I found this one spot - there's a via in the signal trace that should be connected to it but it's grounded. The boardview indicates that it should be connected to the signal and not ground (please see pics attached). None of the other points via is connected to show a short.
Have I reached another layer...
Comment