Disassembly/Repair of the mobile device Doogee T3 with each step description and the required set of tools.

Just slide the back cover down. 

Remove the battery. Also, try not to use a metal tool to pry the rechargeable battery or do it carefully.

Using a screwdriver (Torx T5), unscrew 8 screws on the sides of the phone and remove the side covers with buttons. 

Using a spudger or a plastic pick, carefully, around the edge, detach the middle cover clips and remove it. Do not insert the tool deeply or bend it, otherwise, the housing or cover may be tampered with or damaged.

⚠️ Look in advance in the picture for the location of the cables for inter-board, touchscreen, display, buttons (if any) under the cover, so as not to damage them accidentally.

Using a screwdriver (Phillips 1.5 mm PH000), unscrew 2 screws at the lower part of the phone.

ⓘ Be sure to note the location of the screws before disassembling. When assembling the device, screwing the screw in the wrong place may damage the device or its part. To avoid damage, the removed screws and individual pieces (as gaskets or brackets) must be laid out in the appropriate order, or the screws and their holes in the phone must be marked with colored markers.

Disconnect the coaxial and sub-screen cables on the daughterboard. Also, pry up the vibration motor and microphone.

⚠️ Do not pull on the cable or pry it with a sharp tool, the connectors are pretty weak and break easily, or the cable falls out of the end (lug).

⚠️ Be careful when removing the cables from the connectors, the cables are pretty thin, and it is easy enough to break them or damage the contact tracks inside. 

Remove the sub-board. It is glued to the frame with metalized tape, so to facilitate the process, the board can be heated a bit.

ⓘ The board contains a charging port (Micro USB), microphone, vibration motor, spring contacts for the speaker, and an antenna unit.

⚠️ It is not necessary to insert the tool under the board when removing the sub-board. Internal components could be damaged.

Using a screwdriver (Phillips 1.5 mm PH000), unscrew 3 screws on the PCB.

ⓘ Be sure to note the location of the screws before disassembling. When assembling the device, screwing the screw in the wrong place may damage the device or its part. To avoid damage, the removed screws and individual pieces (as gaskets or brackets) must be laid out in the appropriate order, or the screws and their holes in the phone must be marked with colored markers.

Turn the PCB over. There is no need to use a lever or try to reach the board by force. Make sure that nothing is getting in the way or holding the board.

⚠️Do not bend the circuit board when removing it or push tools under it. Unbeknownst to yourself, you can damage components or cables from the inside.

Pry up the coaxial cable connector and remove the PCB.

ⓘ On the display frame, in the upper part, remains the earpiece speaker.