Xiaomi Redmi smartphones are famous for their balance between cost and performance, but over time, even reliable devices require intervention. The Redmi S3 model is no exception: falling to a hard surface or prolonged operation often leads to the need to replace broken glass, a failed battery or a damaged display plume. Self-disassembly of the device is a great way to save money on the services of a service center, if you have basic skills with small electronics.
The process of dismantling the Xiaomi S3 body has its own technical features that distinguish it from the older or, conversely, flagship models of the manufacturer. It uses a combined design of mounting elements, where some parts are held by screws, and some by tight latches and adhesives. It is critical to understand the sequence of actions, as careless handling of fragile plumes can lead to the final failure of the device. In this guide, we will examine each step in detail, from tool preparation to complete dismantling of the main nodes.
Before you start, you need to get rid of the extra clutter and provide good lighting. You will work with very small parts, and losing even one screw can be a problem when you build. You should also prepare a magnetic mat or a container with cells to sort the fastener, since the screws in the Redmi S3 can have different lengths and threads, and their entanglement can damage the threads in the plastic racks of the case.
Tools and workplace preparation required
For high-quality and safe disassembly Xiaomi Redmi S3 you will need a specialized set of tools that minimizes the risk of damage to the body and internal components. Standard household screwdrivers may not be enough, as screws in modern smartphones often have specific hats, such as the Torx star. Using an inappropriate bit can rip off the snags, after which it will be almost impossible to unscrew the screw without drilling.
The second important aspect is the tools for working with adhesive joints and latches. The back cover and display module are often planted on double-sided tape or special glue B-7000. They require heating to safely separate, so the presence of a thermophen or at least a quality heating pad is a prerequisite. Plastic mediators (scapula) are necessary to uncouple parts of the case without scratches, which will inevitably remain when using metal objects.
Be sure to take precautions when working with lithium polymer batteries. Before starting any work, the device should be completely turned off. If the battery is swelled, work should be done with the utmost care, since puncture of the shell can lead to fire, it is also recommended to have tweezers with curved ends to extract small parts and isopropyl alcohol to clean surfaces of old glue.
☑️ List of disassembly tools
Removal of the back cover and dismantling of the main board
Redmi's disassembly process S3 It starts with removing the back panel, which in this model is mounted on the latches around the perimeter and possibly on adhesive basis. SIM-cards and memory cards so as not to damage their mechanism when heating or pressure on the body. 2-3 for a few minutes, trying not to overheat the central part where the electronic components are located.
Once the glue has softened, use a suction cup to create a small gap between the lid and the frame at the bottom of the smartphone. Insert a plastic blade gently into the resulting gap and guide it along the edges, gradually snapping the locks. Don't put too much effort: if the lid doesn't lend itself, it's better to add a little more heat than risk plastic breaking. Inside, you'll see a plastic frame covering the main board and battery.
The next step is to remove the bottom plastic plate, which is fixed by several screws. Unscrew all visible fasteners, paying attention to their length, because long screws can damage the motherboard if you screw them into short holes. After removing the plate, you open access to the plumes. The first thing you need to disable the battery plume to de-energize the device. Only then you can disconnect the plumes of the display and touchscreen.
⚠️ Warning: Never try to disconnect the plumes by pulling them over the flexible part itself, which will cause the conductive tracks to rupture. Use a plastic blade or nail to plug the connector from the bottom up.
Replacement of the battery and work with adhesive joints
In the Xiaomi S3, the battery takes up a significant portion of the interior space and is often fixed with powerful double-sided tape. Over time, the glue can dry or become too sticky, making it difficult to extract the battery. Under no circumstances do you try to tamper with metal tools or exert force by bending it. Damage to the lithium polymer cell can cause short circuits and thermal acceleration.
To safely remove the old battery, it is recommended to use special Pull-tabs if they are preserved, or to warm the back wall of the case in the battery area. You can use isopropyl alcohol: carefully drop a few drops under the edge of the battery and wait until the liquid dissolves the adhesive layer. This will greatly facilitate dismantling. After removal, be sure to clean the landing place of the residue of old glue before installing the new cell.
When installing a new battery, make sure that its connector matches the original in terms of contact location and voltage. The smartphone power controller is sensitive to voltage drops, so using substandard copies of the batteries can lead to unstable operation of the device or its complete failure. Secure the new battery with a new layer of double-sided tape or special glue strips, providing a tight fit, but leaving room for possible expansion of the battery when heated.
How to check the quality of a new battery?
Disassembly of the display module and glass replacement
Replacing the display in the Redmi S3 is one of the most difficult operations, since the screen is often integrated into the frame or glued to it. If only the glass is broken and the image and touchscreen work correctly, it is theoretically possible to replace only the glass replacement, but this process requires a separator and experience. At home, most often change the entire module assembled with a frame, which is much easier and more reliable.
To remove the module, you must first remove all the screws that lock it around the perimeter and turn off the plumes, as described earlier. If the module is held on glue, you will need heating again. Be careful with the top plume, which can pass under other elements. When installing the new module, check the integrity of the sealing gum, which protects the internal components from dust and moisture. In the Redmi S3 model, the touchscreen plume often goes in a separate connector next to the display plume, do not confuse them when connecting.
After installing the new module and connecting the plumes, take your time to twist all the screws and glue the lid. Test the device. Check the operation of the touch layer in all areas, the absence of broken pixels and the correct operation of the speaker, which is often built into or adjacent to the design of the screen. Once you are convinced of the performance, you can proceed to the final assembly, applying a new layer of glue B-7000 around the perimeter of the frame for tightness.
Diagnostics and replacement of additional components
In addition to the main nodes, other components such as the vibrator, main speaker or microphone can also fail in the Xiaomi S3. Often the sound problems are not related to the breakage of the speaker itself, but to oxidation of the contacts or clogging of the speaker grid. To diagnose, use a multimeter in vertebrae mode: the resistance of a working speaker is usually 32 Ohms (for the main one) or slightly more for a conversational one.
A vibro motor replacement is required if the phone has stopped vibrating when making calls or notifications. In this model, it can be built into the bottom plume or be a separate module. When replacing, make sure that the new vibro motor has similar dimensions, as even a millimeter mismatch can cause it to press on other components or not to stand in place.
Special attention should be paid to the charging plume (bottom board), which is the way the device is charged and transmitted in hands-free mode. A common problem is the oxidation of the USB Type-C connector or microphone. The replacement of this board is easy: just unscrew a few screws at the bottom of the case. Before installing the new board, clean the speaker hole from dust so as not to worsen the sound.
| Component | Difficulty replacing | The necessary tool | Risk of damage |
|---|---|---|---|
| Battery | Medium | Thermophen, spatula, alcohol | High (fire risk) |
| Display module | Tall. | Sets of screwdrivers, suckers | Medium (risk of chipping) |
| Back cover. | Low. | Suction, mediator. | Low. |
| Lower fee (USB) | Low. | Phillips screwdriver | Low. |
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The main difficulty of dismantling Redmi S3 is the work with adhesive joints and fragile plumes, requiring patience and accuracy, not physical strength.
Device assembly and initial start
The Redmi S3 is assembled in reverse disassembly. Set the motherboard in place, making sure all the screw struts match the holes. Connect the display, touchscreen and battery plumes. When twisting the screws, be moderate: plastic cracks easily when stretched, and a weak puff will lead to a backlash of the board and possible separation of contacts when dropped.
Before installing the back cover, be sure to check all functions: camera, speaker, microphone, vibration and proximity sensor. If everything works correctly, apply a thin layer of B-7000 glue or use a new double-sided tape around the perimeter of the frame. Press the lid tightly and lock the device with rubber rings or load for 15-20 minutes before the initial grasp of the glue.
After assembly, turn on your smartphone and let it work for 10-15 minutes, controlling the temperature of the case. Excessive heating may indicate poor contact of plumes or improper installation of the battery. If the device is stable, you can consider the repair successfully completed. Regularly check the status of the battery in the first days of operation.
⚠️ Warning: If the phone doesn't turn on after assembly, don't try to charge it right away. Check for the battery plume connection and no foreign objects (such as a forgotten cog) under the motherboard that could have caused a short circuit.
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Use blue tape or special heat-resistant stickers to fix the plumes on the board after you connect, which will prevent them from accidentally disconnecting when the phone vibrates or falls in the future.