Disassembly/Repair of the mobile device Xiaomi RedMi 4 with each step description and the required set of tools.

Using a screwdriver (precision star-shaped 0.8 mm aka Pentalobe), unscrew/drive 2 screws out at the end of the phone.

Use the ejection tool (aka Needle) or Paperclip. Push the tip all the way into the hole until the tray ejects, and then pull the tray of SIM and Memory card (Micro SD) out.

⚠️️ Pay attention! The tool must be inserted into a hole on the edge of the phone's housing. Do not press too hard. It may break the tray eject mechanism.

Using a spudger or a plastic pick, carefully, around the edge, detach the back cover clips, and open it.

After, we disconnect the fingerprint sensor connector and remove the back cover.

Do not insert the tool deeply or bend it. Otherwise, the housing may be tampered with or damaged.

⚠️️ Be careful when opening the cover from the volume and power buttons side. Thin cable and fragile buttons are straightforward to damage.

⚠️️ Pay attention to the fingerprint sensor cable located on the inside.

Using a screwdriver (Phillips 1.5 mm PH #000), unscrew the six screws.

Pry over the edges. Move an opening tool along the edge detach the clips and remove the cover.

Disconnect the battery connector as soon as possible. It is better to use a non-metal or plastic tool to avoid any damage.

ℹ️️ The Xiaomi RedMi 4 model has a battery BN42 with 4000 mAh capacity (aka rechargeable battery).

With extreme care, remove the battery because it is glued from the inside by the manufacturer.

Also, we need to remember or look in advance at the location of the flat cables under the battery, so as not to damage them.

Using a screwdriver (Phillips 1.5 mm PH #000), unscrew the six screws. One screw is short and black, remember its location so you don't damage something when reassembling.

Pry at the edge and remove the cover hiding the sub-board.

Disconnect the coaxial cable connector, inter-board cable.

Remove the sub-board. It may be glued to the frame or attached with attachments like latches or hooks, so be careful.

ℹ️️ The sub-board contains a charging port (Micro-USB), microphone, spring contacts for the speaker, and an antenna unit.

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

Pry over the edge and remove the loudspeaker assembly.

Using a screwdriver (Philips 1.5 mm PH #000), unscrew one screw securing the motherboard.

Disconnect the connector on the motherboard, and remove the front (selfie) camera.

Pry up the connectors of the side buttons cable, display cable, touchscreen cable, inter-board cable, and coaxial cable.

⚠️️ 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.

Carefully remove the printed circuit board. There is no need to use a lever or try to reach the circuit board by force. Make sure that nothing is getting in the way or holding the circuit board.

The motherboard, also, may be attached with attachments like latches or hooks, be careful.

⚠️️ 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 over the edges and detach coaxial cable.

Unstick the side buttons cable.

Pry at the bottom and remove the vibration motor.

⚠️️ Be careful! The vibration motor is glued a bit with adhesive.

Pry at the bottom and remove the earpiece speaker.

⚠️️ Be careful! The earpiece speaker is glued a bit with adhesive.

⚠️️ If we pry the speaker in the middle we may break the earpiece speaker in half.