New Digitizer without replacing the LCD?
Is it possible to fit a new digitiser to the Sony Xperia Z3 without replacing the LCD? I know they can be purchased separate, but my original seems to be bonded to the LCD.
It is possible.
The tricky part is to get the LCD off the device without damaging the LCD.
Heat (around 80°C) will loose the adhesive and makes it easier for you to separate the LCD-Unit from the frame.
After you got the LCD-Unit off of your device, you can separate the glass (Digitizer) either with a LCD-Separator (costs around 200-300€) and a molybdenum wire or with playing cards (search on youtube for tutorials to see what I mean).
After that you need to remove the remaining glue off the LCD wihtout damaging it. You can use your finger (like a rubber / eraser for pens) or some tools like plastic razor blades and glue remover or 99% alcohol and so forth.
As soon as your LCD is free of glue, test it on the device. If your LCD is still working, you need to glue the digitizer onto the LCD.
Therefor you can use LOCA, but the glue will probably run between your LCD and Backlight and destroy the Unit or respectively create some discolorations.
A better method is to use OCA, but thats nothing you can do at home, because you will need special machines for that method.
And thats all. If you do all the steps successfully your LCD and Digitizer should work fine and be ready to use. But its way more safe to buy the whole LCD-Unit (LCD and Digitizer combined).