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In last 2-3 years after trying out for some action, the same LCD panel started to suffer from new old problem again with failing LCD inverter.
After some investigation I found that the inverter's fuse F1 blows shortly after CCFL lights up and flickers, probably due to some coil problem like a short in one of it's windings and/or a dying tube that struggles to light up (not sure on this).
I tried several used LCD inverters from other 770 and 770X, but always result in similar blackout problems after some time of using.
In last couple weeks I tried to restore this panel for good, but unfortunately found that it got another problem the also know as "vinegar syndrome".
Sadly it was showing a very bad image, full of stained zones and cracks, and "in top of the cake" a dead vertical line of pixels on LCD matrix... nothing could be done to save it in that state because even after removing the polarizing filter (totally brittle as seen in picture) the matrix isolation over the glass was also bulgy and yellow deteriorated.
The recover of the LCD panel for my 770 began again but this time from scratch.
Fortunately I find a used but fine 13.3" replacement panel with perfect matrix and polarizer filter. Although having a reddish backlight I was no worried because I was planning to do a LED backlight conversion/swap, a retrofit that gives some reliability to it.
After some searching, I found and somehow gamble on a LED backlight kit for my LCD panel that was not too pricey at Aliexpress.
I choose the 275mm LED strip length option that approximates just below the length of the original ~280mm CCFL tube in order to be easy to fit and mostly to avoid any damaging modification on the LCD frame, as in my previous experience with a replacement a little longer CCFL tube than the original ended up...
Here are the steps taken to achieve it, assuming that LCD panel is already out of the display cover case, hinges and disconnected from inverter board:
Remove CCFL:
1 - Remove all screws on the back of the panel;
2 - Disconnect the flat cable of the lateral back PCB from the top one;
3 - Slightly release metallic frame latches about 1mm on top and sides in order to lift and detach the white plastic LCD support, beginning from the top, and sliding out from the bottom;
4 - Gently detach the CCFL tube cable from it's installed path and hanging external supports of the long cable;
5 - Tilt the lateral back PCB to provide a way to freely lift for about 2mm the CCFL refective "case" from the white LCD support and remove the CCFL tube by sliding the left rubber end tube support.
6 - Cut the wire cable from the tube in order to allow it's removal from the right side together with the short wire.
6 - With tube out, remove the central transparent o-ring and push the rubber support from the tube end carefully sliding through the short cable in order to cut the now exposed wire.
Installing LED strip:
1 - The right end rubber support has to be cut in length with a razor in order to allow passing through the pair of wires on the new LED strip;
2 - Install the o-ring in about half length on the LED strip in order center it's position on the lamp case;
3 - Tilt again the lateral back PCB to provide a way to freely lift for about 2mm the CCFL "case" and slide the LED strip from right side. It helps if the cable is previously bend with 90º angle up to the front of the LEDs in order guide to the correct path and at the same time set a better center position long wise and direction of the LED light;
4 - Place the left rubber end on its original position, it should catch the tip of the LED strip end;
5 - Let drop into place the white LCD support and assure that the lamp case is fitted on it's place, install the lateral back PCB and connect its flat cable to the top PCB;
6 - Slide in from into the bottom part the metallic frame the white LCD support and assure all latches are securing it when pushed into;
7 - Install all screws on back.
Connect the LED driver on the original inverter:
1 - First make sure the inverter's fuse F1 is not blown (in case it's faulty to light up a CCFL tube), if yes then replace it with an "short blowing" type and 1.6A rated one;
2 - Solder the VCC (shown brown) cable wire from driver on inverter's F1 fuse lower pad (far from edge) where is a 15v supply;
3 - Solder the ENA (shown yellow) cable wire on upper left pad of the sliding potentiometer to have light on/off control where 5v/0v is supplied ;
4 - Solder the ADJ (shown white) cable wire on bottom left pad of the sliding potentiometer to have brightness control where voltage ranges from 5v to 0v (minimum to maximum respectively);
5 - Solder the GND (shown black) cable wire on shield of the sliding potentiometer;
6 - Test the installation of the driver on left side of the LCD panel between it's hinge and cover. If wire is short, cut and extend the LED strip pair or wires;
7 - With double face adhesive tape secure the LED driver PCB and pass the cables on available space on the back of the panel, it is tight it has enough clearance.
After this whole procedure, the swapping from CCFL to LED backlight proved to be a tight and good solution as the displayed image seams to have good backlighting intensity with a slight and almost unnoticeable dim on the bottom corners, and surprising evenness through it's length.
The brightness control now in half way is more than enough, similar to CCFL highest brightness, and in maximum position some heat is generated (like CCFL tube also causes), a thing that I want to avoid because it could be harmful and provoke deterioration of panel's materials.
I hope that this helps someone who want to give more life on their Thinkpad 770 LCD panels, at least in 13.3" size example.
130,220,230,235,240/x/z,310ED,315,330C/Cs,340,345c,350,355c,360c/pe/cse,365x/cd/e,370c,380/d/z,390/e/x
510,555