Disassembly/Repair of the mobile device Xiaomi RedMi Note 12S (Xiaomi RedMi Note 12S 23030RAC7Y) with each step description and the required set of tools.

⚠️️ Before disassembling, do not forget to turn your phone off.

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.

We need to heat the surface of the back cover to a temperature of about 70° C or 160° F. For this we use a heating mat, you can use a hair dryer.

And after 5-7 minutes we can proceed to disassembly.

To remove the back cover, we will use a thin plastic film, this is the protective film from the new display. We insert it into the gap between the middle cover and the back cover and run it lengthwise to detach the cover.

⚠️️ We need to be careful around the cameras. As the back cover is separated from the cover of the cameras, the back cover will be glued around the cover of the cameras.

⚠️️ We also need to be careful in the area of the side buttons and the fingerprint sensor, because there may be cables located.

Using a screwdriver Phillips 1.5 mm (PH#000), unscrew the two screws securing the cover of the cameras.

Now we need to detach the cover of the cameras with a non-metal tool. Carefully slip the thin tool under the cover and detach the clips securing the cover.

On the cover we can see the flashlight elements.

Disconnect the fingerprint sensor cable connector.

⚠️️ It is better to disconnect the connector right now to avoid damaging the fingerprint sensor cable or connector when we will detach the middle cover.

Using a screwdriver Phillips 1.5 mm (PH#000), unscrew the seven screws on the upper cover.

We also unscrew the six screws on the bottom part, using the same 1.5 mm Phillips screwdriver.

One screw we will leave - it holds the loudspeaker.

And we move on to detach the middle cover, we use a plastic film.

We run the film into the gap near the hole of the cards tray, creating a space large enough to keep working. And then we can use a thicker tool, and run it along, detaching the clips.

It is necessary, as always, to be careful in the area of side buttons and a fingerprint sensor and in the area of cameras, so as not to damage anything. We also need to be careful on the corners, because the cover is held especially tightly on the corners.

On the cover we have the fingerprint sensor and contact pads and antenna transmission lines.

Disconnect the battery connector as soon as you can. Use a non-metallic or plastic tool to avoid any damage.

ℹ️️ The Xiaomi RedMi Note 12S 23030RAC7Y model has a battery BN5D with a capacity of 5000 mAh (also known as a rechargeable battery).

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

Pry at the edge and remove the loudspeaker assembly.

We need to disconnect the inter-board cable connector, the coaxial cable connector and the display cable connector.

⚠️️ 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).

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, vibration motor, and an antenna unit.

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

And we can detach the cameras. The front camera is traditionally glued to the shield on the motherboard on a copper heat dissipating film.

It is better to hold the cameras by the body and preferably not to touch the lenses.

Disconnect the coaxial cable connector, bend it aside and disconnect the inter-board cable connector.

We can remove the motherboard. Find the right and convenient place for us, hook at the edge and pull out the motherboard.

On the back side, the motherboard may be held on by thermal paste.

Finally, we move on to detach the battery.

We need to unwrap the brown tabs A and B and read which one we need to pull for. And as it becomes clear to us from the description, we have to pull the wide tab A upwards. With one hand we hold the display frame, and with the other hand we gently pull the tab with the letter A upwards, detaching the battery.

As we can see, the battery is also held on the transparent protective coating, which protects the inter-board cable.

ℹ️️ In the display frame remained: the earpiece speaker, coaxial cable, inter-board cable, vibration motor, side buttons.