Although the parts are small, and it takes a little bit of time to complete, you can replace the digitizer and screen assembly for your Nexus 7 without much trouble. To begin, you will need to be sure you ordered the correct screen assembly.
Here’s the link to a Nexus 7 Tablet LCD Display Touch Screen Digitizer assembly but you will need to make sure you order the kit that best meets your needs. You will also need some tools for this. This is an awesome set of screen replacement tools
that are very inexpensive, less than $10 at the time of writing.
You need small plastic pry tools as linked above, a few screw drivers, and a guitar pick or similar prying tool. You will use these to separate the small Nexus 7 parts.
Start with a small prying tool we will work along the top, left the back and the right side.
Then attempt to pry open the top right corner, using the guitar pick, as it will be easiest to use. You may even be able to use your fingernails if you don’t have the repair tools. Once you have a small crack, you can continue prying it open, working down the left side near the power/volume, then slide the tool down to separate the shell completely set aside the back plate.
Remove the battery by slowly rocking the power connector left to right to unplug it from the motherboard connector. Set it aside for the rest of the project.
Next, the black tape holding the lcd connector can be pried up with a flat head screwdriver, just be careful not to damage the Nexus 7 motherboard or its circuitry. Once you get an edge
of the tape up, just use your fingers to grasp it and pull it up the rest of the way. If you lift up the small metal cover on accident, just move it aside. Next we will remove the Nexus 7 lcd display cable.
Work your pryer underneath the cable and gently move it back. The other two ribbon connectors are next. Release the pressure connectors by prying the release up on both then slide them backwards.
Next, remove the screws that are arround the body of the Nexus 7. A small philips screwdrive will remove these, after they’re out, remove the mobo from the LCD panel. The bezel is also attached, but the board can be carefully removed. What is left is the lcd and digitizer. These are attached to the bezel. Be careful disconnecting these if you bought a replacement assembly without the bezel as you will need to re-use it.
Set the bezel/lcd/digitizer in the sun to let it heat up the to loosen the adhesive. After 30min-45min or so, slowly and carefully, work your way around the perimieter removing the panel without breaking it. you want to keep the adhesive on the bezel since it will be used when re-assembling. Take your time with this part. be careful near any cracks you may have on your old screen.
If your screen is cracked and you haven’t left the assembly in the sun long enough, you will have a lot of little shards of the screen you will need to remove prior to reuse. If these pieces aren’t removed your new Nexus 7 screen assembly will not seat correctly on the bezel.
Now to install the new display. Align it with the bezel and carefully plug the connectors back in. You may need to use a piece of the heatshield from the old display to help reseat the connector.
After it’s connected, replace the motherboard and Nexus 7 body onto the display. After it is replaced, make sure it is a tight fit and put the screws back in.
After you get it back together, you can re insert the battery and attempt to power it on! If it powers on, and you can see the display, using the touchscreen, it’s back to working!
If not, you most likely need to check your cable connections inside.