How to disassemble Xiaomi Redmi Note 9S: step-by-step analysis

Modern smartphones are becoming more difficult to maintain, and the Xiaomi Redmi Note 9S model was no exception. The dense layout of the internal components requires the wizard not only the accuracy of movements, but also a deep understanding of the architecture of the device. Before starting any manipulations, you need to clearly understand the risks associated with leakage of the case and possible damage to fragile plumes.

The main purpose of disassembly is often to replace the battery, repair the charging connector or recover from moisture. It is important to understand that self-dismantling deprives the owner of a warranty if it has not expired. However, for experienced users or service center specialists, this process is a routine procedure that requires only a follow-up.

In this article, we will look at each stage of dismantling in detail, paying special attention to hidden screws and the features of peeling off the back cover. Proper preparation of the workplace and the presence of a specialized tool is 90% of the success of the operation. The heating temperature of the rear cover should not exceed 90 degrees Celsius, so as not to damage the structure of the polycarbonate and the adhesive layer.

Workplace preparation and tools

You can't do a good job of disassembling without a properly equipped space. You need a clean, well-lit table, preferably with an antistatic coating or a mat. Any small piece that falls on the floor can make it impossible to put the device back together, so order is key to success.

The toolkit should be tailored to the specifics of modern Xiaomi smartphones. Using inappropriate screwdrivers can lead to slicing of the screw faces, which will greatly complicate further repairs. It is also critical to have a suction cup or a special mediator on hand to open the case.

Here is a list of the necessary equipment:

• 🔧 Precision screwdrivers (cross-haired) PH000 Torx T5)
• 🔥 A hair dryer or heating platform for softening glue
• 💳 Plastic card or mediator for opening the case
• 🧲 Magnetic mat or organizer for sorting screws
• 🧴 Isopropyl alcohol and sucker

Keep in mind the safety of lithium-ion batteries, as damage to them can lead to fire, and always keep a fire extinguisher or sand tank handy in case of an emergency.

⚠️ Warning: Before starting any work, be sure to turn off the smartphone. Attempting to disassemble the enabled device can lead to a short circuit and the motherboard fails.

Rear cover removal and removal SIM-tray

The first step in the process of dismantling the Redmi Note 9S is the extraction of the tray for SIM-This action relieves the internal stress in the structure and prevents accidental damage to the contacts when the case is bent. Use a special paper clip included in the kit, or a thin sting of the screwdriver.

Once the tray is removed, the perimeter of the back cover must be heated; the adhesive layer that holds the panel softens when exposed to temperature; the hair dryer movements must be circular, uniformly warming the entire area of glass or plastic; do not hold the flow of hot air at one point for too long.

Place a suction cup at the bottom of the back cover, closer to the center, and gently pull upwards, creating a small gap. Insert a mediator or a thin plastic card into the resulting slit. Lead the instrument along the perimeter, cutting the adhesive layer, but be careful in the area of the main camera module.

Pay special attention to the area around the camera lenses. Here the glue can be applied more abundantly, and the risk of damage to the glass elements of the lenses is maximum. If the lid does not lend itself, add a little more heat, but do not use brute force.

Removal of the protective panel and disconnection of plumes

Once you successfully remove the back cover, you'll see a black plastic panel that covers most of the components, and it'll be attached to a lot of screws of different sizes and types, and it's critical to sort them out as you unscrew them, because entanglement of long and short screws can cause the board to break down.

Use the PH000 screwdriver to twist the main fasteners around the perimeter and in the center. Some screws may be hidden under decorative plugs or stickers, carefully examine the surface. After removing all screws, carefully lift the panel, starting at the bottom edge.

The first thing to do after removing the protection is to turn off the battery, which will turn off the device and protect the power chain from accidental power surges, the battery connector is located at the bottom of the motherboard and is often closed with an additional metal plate.

The sequence of disconnection of the plumes shall be strict:

• 🔋 Battery plume
• 📱 Main plume of the display
• 🔌 Fee of the child charge (charging)
• 📡 Antenna contacts (if not disconnected with the fee)

To turn off, use a plastic blade, avoiding metal tools that can close the contacts. Press the connector vertically upwards, without swaying it from side to side so as not to break the latches.

⚠️ Warning: Never try to turn off the plume by holding it by the flexible part itself. Take a rigid plastic connector, otherwise there is a risk of detachment of the conductive paths.

Access to motherboard and cameras

The motherboard in the Xiaomi Redmi Note 9S is located at the top of the case and is closed with an additional metal screen, which not only protects components from mechanical stress, but also serves as a radiator to remove heat from the processor.

To remove the screen, you need to twist a few screws around the perimeter, and underneath these may be ground contacts, which are important not to lose, and once the metal is removed, you can access the main modules, including the processor, memory and camera modules.

The main camera module is attached to a separate plume and may have an additional lock. Before extracting, make sure that all screw mounts of the camera frame are twisted. Movements should be smooth, without jerking.

When working with cameras, try not to touch the surface of the lenses with your fingers, as greasy marks are difficult to remove without disassembling the optical system. If there is dust on the lens, use a pear to purify, but do not rub the surface.

Removal of the battery and replacement of elements

Replacing the battery is one of the most common reasons for disassembling a smartphone. In the Redmi Note 9S model, the battery is attached to double-sided tape, which hardens over time. A simple effort here won't help and can be dangerous.

It is recommended to use isopropyl alcohol by dripping a few drops under the edge of the battery through the resulting gap. The liquid will penetrate the structure of the adhesive and weaken its grip. Wait 2-3 minutes before starting extraction.

Use a plastic card or a special spatula to lift the battery. Move gradually, starting from one of the corners. If you feel strong resistance, add more alcohol or warm up the case slightly on the front side (carefully!).

Critical moments when working with the battery:

• 🚫 It is strictly forbidden to pierce the battery case with a needle or knife.
• 🚫 You can not bend the battery or apply point pressure to it.
• 🚫 It is forbidden to use metal tools for tampering.

After removing the old battery, clear the seat of the residue of the old glue.The new battery should be installed on fresh bilateral tape, which usually comes complete with the spare part.This will ensure reliable fixation and normal heat sink.

⚠️ Attention: If the battery is swelling, you need to remove it with triple care. Any damage to the shell can cause the electrolyte to ignite.

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Keep the original safety plate from the old battery if the new one doesn't. If you rearrange the protection and the plume, you'll get a full replacement compatible with the power controller.

Assembly of the device and verification of functionality

The assembly is done in reverse disassembly, but there are some nuances, and first of all, check all the plumes for clutter and contamination of the contacts, even a microscopic speck of dust can disrupt the connection.

When installing the back cover, apply a new layer of glue or use special adhesive tapes around the perimeter. The old glue is better removed completely, as it will not provide the desired tightness. Spread the adhesive layer evenly, avoiding cameras and sensors.

After you snap the case, don't rush to turn on your smartphone. Let the glue grab for 15-20 minutes, you can put the device under a light press (for example, a few books), then plug the charger and check the reaction of the indicator.

Checklist:

1. Battery test.
2. Testing for the presence of "dead zones".
3. Checking all cameras and autofocus.
4. Test of speakers, microphone and vibrator.
5. Checking the operation of proximity and lighting sensors.

If all functions are working correctly, the repair is considered a success, and if you have problems such as a lack of network or a broken sound, you will have to re-disassemble the device to check the connectors.

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Quality assembly depends not only on the correctness of the connection of the plumes, but also on the purity of the contacts and the reliability of the adhesive connection of the rear cover.

Frequently Asked Questions (FAQ)