As you work, try not to accidentally power on the phone. If you do, turn the phone off before resuming disassembly.
Place a suction cup near the bottom edge of the display.
Pull on the suction cup with strong steady force.
Press the edge of an opening tool straight into the frame seam near the suction cup until the edge wedges between the plastic frame and the back cover's lip.
Due to tight tolerances, this will take substantial force. Using a new opening tool with an unmarred edge will help with this step.
Do not use metal tools, as they will most likely crack the screen.
Continue sliding the opening tool along the long edge, releasing the clips along the way.
The last clip in the top-left corner near the alert switch is recessed and can be difficult to release. Take your time and use the flat end of a spudger or an opening pick to help.
Use the point of a spudger to pry up and disconnect the battery connector from its socket, located above the top right corner of the battery pack.
Bend the connector away from the socket to prevent accidental contact.
To re-attach press connectors like this one, carefully align and press down on one side until it clicks into place, then repeat on the other side. Do not press down on the middle. If the connector is misaligned, the pins can bend, causing permanent damage.
Carefully bend the still-attached daughterboard flex cable away from the battery.
During reassembly, make sure that the Main labeled connector connects to the motherboard. The Sub connector will fit the motherboard socket but it will cause your phone to malfunction.
Use the opening tool to push any adhesive tape holding the battery to the edge of the plastic frame. There should be at least one on each battery side.
Be careful not to puncture the battery pack with the tool.
Remove the battery and any remaining adhesive residue on the frame.
Do not reuse the battery after it has been removed. Reusing a battery that is bent or otherwise stressed is a potential safety hazard.
If your replacement battery did not come with a pull tab, you can transfer the old tab to the new battery to help with subsequent replacements.
While installing a new battery, temporarily connect the battery to the phone to ensure proper battery alignment.
To install a new battery onto an existing frame, remove some adhesive strips from a pre-cut adhesive card, or cut some strips from a roll of Tesa tape, and stick them in the highlighted area.
If you are installing a battery onto a new screen and digitizer assembly, be sure to peel off the orange adhesive liner to expose the battery adhesive for the new battery.
Use the point of a spudger to pry up and disconnect the capacitative buttons connector from its socket on the daughterboard, which is located below the battery.
Repeat the process to disconnect the fingerprint scanner connector from its socket on the daughterboard.
Try not to tear the black tape pieces so that you can reuse them during re-assembly. If you do tear the tape, replace them with pieces of electrical tape.
Use the point of a spudger to pry up and remove the black tape covering the volume buttons on the right edge of the phone.
Repeat the process with the black tape covering the power button on the left edge of the phone.
Use the flat end of a spudger to gently push the volume button board away from the frame.
If the volume button board begins to bend significantly, stop and pry from a different angle.
Continue prying until you loosen the volume button board from the frame.
To reinstall the volume button board, cut a small piece of adhesive from the pre-cut adhesive card or a roll of Tesa tape, and use it to stick the board back onto the frame.
Use the point of a spudger to pry and loosen the power button from the left edge of the frame.
To reinstall the power button, cut a small piece of adhesive from the pre-cut adhesive card or a roll of Tesa tape, and use it to stick the button back onto the frame.
Lift the volume flex cable upwards from its position, removing it from its groove.
Remove the volume and power button assembly.
If you are transferring the assembly to a new screen and digitizer, remove the blue adhesive liner on the replacement frame and press the cable onto the exposed adhesive.
Be sure that the earpiece speaker is correctly oriented in its recess such that the gold contacts point upward.
Place the earpiece speaker into its recess and firmly press it into place with your finger.
If you are transferring the earpiece speaker onto a replacement frame, be sure to remove the earpiece speaker adhesive liner on the replacement frame to expose the adhesive.
May I kindly ask, both oneplus 3 and oneplus 3T are the same screen? I'm about to buy a screen with frame and digitizer, and all sellers name their products "oneplus 3/3T LCD screen".