How to disassemble the Xiaomi Redmi 9 Pro phone: a step-by-step guide

The process of disassembling a modern smartphone is always a balance between the desire to save on repairs and the risk of damaging fragile components. Xiaomi Redmi 9 Pro model was no exception to the rule: the device has a dense layout and a glass back cover, which requires the master to be more accurate and have a specialized tool. Before starting to dismantle, you need to clearly understand that any interference with the internal structure of the gadget automatically voids the official manufacturer's warranty.

The main challenge is that the device is assembled with high-quality, but very sticky adhesive, and many plumes are located in hard-to-reach places under metal screens. Incorrect handling of heating elements or excessive force when cracking modules can lead to cracks in the display or damage to the motherboard. In this article, we will look at each step of the work in detail to minimize the risks and successfully replace the failed parts.

First, you need to prepare a workplace: a desk with good lighting and an antistatic mat, if you can. The lack of static is critical, because electronic components are extremely sensitive to discharges that the human body may not even feel, but for chips they are fatal. Also make sure that you have all the necessary tools at hand, which will be discussed in the next section.

Tools and workplace preparation required

The use of improvised tools such as knives or pins is strongly discouraged, as they can easily damage flexible plumes or scratch the internal frames. The minimum set includes a heating appliance for softening the glue, a sucker, a set of plastic mediators (scapula) and a cross screwdriver of the right size, usually a PH00 or PH000.

Special attention should be paid to the organization of space, all screws should be folded into a special magnetic mat with markings or in separate cells, signing the dismantling steps, which will help to avoid a situation where there are unnecessary parts during assembly or, worse, screws of different lengths will be screwed into the wrong holes, which can penetrate the motherboard through.

• 🔧 A set of precision screwdrivers with magnetic tips for working with small fasteners.
• 🌡️ Thermostol or building hair dryer with the ability to adjust the temperature to heat the perimeter of the housing.
• 📱 Plastic blades and mediators for safe opening of the body without scratches.
• 🧲 Magnetic card or organizer for sorting screws of different sizes.
• 🧤 Antistatic gloves and tweezers with dielectric linings at the ends.

⚠️ Attention: Using a normal household hair dryer will not give the desired effect, since it is not able to heat the glue to the required 80-90 degrees, and a building hair dryer without temperature adjustment can melt plastic elements of the frame.

Before starting physical actions, be sure to turn off the device and remove the tray. SIM-This is a standard safety procedure that prevents the phone from accidentally turning on and shorting when the battery is turned off. If the screen is broken and does not respond to touch, make sure the phone is completely discharged or forced off with a combination of buttons before starting heating up.

Removal of the back cover and primary access

The most time-consuming step is to separate the back from the frame, and the glass is attached around the perimeter to double-sided tape and glue, which over time becomes polymerized and very durable, and the heat should be produced evenly, leading the heat source along the circuit of the device during the course of the process. 2-3 avoiding concentrating hot air in one point so as not to damage OLED-battery.

After enough warming, insert the suction cup into the bottom of the back cover, closer to the edge, and gently pull up, creating a small gap. Insert a thin plastic mediator into the resulting gap immediately and, without removing it, start leading along the faces, gradually cutting the adhesive layer. The movements should be sliding, parallel to the plane of the screen, so that the blade does not go deep into the body.

Be especially careful in the area of the main camera module, as there are often additional mount elements or plumes that go to the side buttons. A sharp jerk can break the thin conductors, after which the volume or on buttons will stop working. If you feel resistance, stop and check if you forgot to unscrew any hidden screws, although in the Redmi 9 Pro they are usually not under the cover at this stage.

Dismantling protective screens and disconnecting plumes

When you successfully remove the back panel, you'll see the inside of it, protected by black plastic pads and metal plates, which protect the connectors from dust and lock the plumes in the right position, and you'll need to carefully twist a lot of small screws, which can be as many as a dozen in different circuits.

The first and most important rule of electronics is to turn off the battery, so even if the phone is off, the battery contacts are put on voltage, find the battery connector, which is usually located in the lower or central part of the board, and gently snap it off with a plastic blade, only then you can safely touch the other connectors and manipulate the motherboard.

Then you have to turn off the other plumes in sequence. You have to notice the latching latches, some connectors need to be pulled up, some connectors need to be pulled up. Metal screens that cover the processor and communication modules, it is better not to remove unless absolutely necessary, because there are small components underneath that are easily lost or damaged by statics. If you want to replace the screen or battery, you do not need to touch the screen of the CPU.

Replacement of the battery and work with the glue layer

In the Xiaomi Redmi 9 Pro, the battery is mounted on two striped tapes. You can't just pull it out -- you can damage the lithium polymer battery shell, which can cause fire or bloating. You need to use special hoods (tabs) that are often designed to safely extract, or warm up the back of the case in the battery area.

If the exhaust bands are missing or broken, gently slap the edge of the battery with a plastic card or a spatula, while heating the area under the battery. Move the tool progressively, trying to cut the adhesive layer, rather than tearing the battery off with a jerk. It is strictly forbidden to use metal objects that can puncture the battery body.

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Before installing a new battery, clean the seat of the remnants of old glue with alcohol or a special solvent so that the new battery lay flat and does not swell from pressure.

When installing a new battery, make sure that the connector contacts are clean and not oxidized. Fixing is better done with a special glue B-7000 or double-sided tape for phones, applying it in thin strips around the edges. Do not pour glue on the center of the battery, as when working it can expand slightly and it needs space.

Removal and installation of the display module

The display module in modern smartphones is a single assembly of glass, touchscreen and matrix. In the Redmi 9 Pro, it is attached to the perimeter of the frame and connects with a flexible plume to the board. Before the final removal of the old screen, make sure that all screws holding the board are twisted and the plume is disconnected, otherwise you risk tearing the connector along with part of the tracks.

Check the new display before installing. Connect the plume to the board (without putting it in the frame permanently) and turn on the phone. Check the touchscreen, the presence of broken pixels and color transmission. If everything works correctly, apply the new glue B-7000 thin stripe around the perimeter of the frame and press the screen, fixing it with rubber bands for 15-20 minutes before drying.

It is important not to overdo it with the amount of glue, as its excess can squeeze out and stain the case or get on the speaker. Also make sure that the plume does not break down and rest on the sharp edges of metal elements, which over time can lead to its rubbing and the appearance of stripes on the screen.

Device assembly and initial start

The assembly is done in reverse order, but requires even more care. Put all the metal screens in their places and twist the screws, keeping the correct length for each hole. Connect the battery last before closing the lid, so that you can check the performance of all systems.

Once the battery is plugged in, press the power button, and if the phone vibrates and the image appears on the screen, the most difficult stage is passed successfully, and check the cameras, speakers, microphone and proximity sensor, covering the top of the screen with your hand during the call.

⚠️ Warning: If the phone doesn't turn on after assembly, don't rush to disassemble it again. Leave it on charge at the station. 15-20 minutes, as the battery could go into a deep discharge during work, and the power controller needs time to activate.

The final step is to glue the back cover. Degrease the frame and the lid with an alcohol napkin, apply a new glue, or use a pre-made adhesive layer (pre-adhesive), which often comes complete with spare parts. Press the lid tightly around the perimeter and lock the device again with rubber bands until the glue is completely solidified.

Frequently Asked Questions (FAQ)