Many budget smartphone owners face the need to repair themselves when the screen is broken and the battery is no longer holding charge. The lid on the Xiaomi Redmi 9A is non-removable, which creates the illusion of not being able to access the insides without special equipment. However, with the right technology of warming up and the point of application of effort, you can carefully divide the case into parts.
Unlike older models with plastic panels on latches, modern Xiaomi gadgets are glued around the perimeter with a durable industrial glue. Trying to open the device “cold” or with a knife is almost guaranteed to lead to chipped glass and deformation of the frame. You will need patience, since the Redmi 9A has a glass back panel that requires special treatment when heated.
In this article, we'll go into detail about the work place preparation process, the tools you need, and the step-by-step algorithm for action. Compliance with temperature is a key success factor that is often ignored by beginners. 85-90 degrees Celsius, so as not to damage OLED-matrix.
Tools and workplace preparation required
Before starting the dismantling, you need to organize a safe space to work. The surface of the table should be clean, flat and preferably covered with a silicone mat, so that small screws are not lost and the glass is not scratched. The lack of static electricity also plays an important role, so it is recommended to use an antistatic bracelet or periodically touch ground metal objects.
For a high-quality disassembly, you will need a specialized set of tools that can be purchased in radio stores or online. Using improvised tools such as kitchen knives or household hair dryers often leads to deplorable results due to uneven distribution of temperature and pressure.
- 🔧 Set of screwdrivers (cross-crosses) PH00 and PH000, triangular Pentalobe for spinning the screws of the frame.
- 🌡️ Thermophen or professional heating pad (separator) for uniform heating of glue around the perimeter.
- 🎴 Plastic mediators and suction cup for careful detachment of glass without damage.
- 💧 Isopropyl alcohol or special solvent of glue (B-7000) remove adhesive residues.
It is important to understand that Xiaomi Redmi 9A has a rather fragile design of the rear panel. If you use a regular hair dryer, it will take much longer to warm up, and the risk of overheating of the internal components will increase. Professional thermophen allows you to direct the jet of hot air point-by-point without affecting the display from the back side.
☑️ Preparation for disassembly
The process of heating and primary detachment of the body
The most important step is to heat the perimeter of the device, the adhesive layer that connects the glass and the frame must soften to a thick, viscous mass. If you warm it poorly, the glass will crack when you try to smack; if you overheat, you can damage the adhesive base of the display or the battery.
Turn on the thermophen at a medium power (about 300-350 degrees at the output, holding the tool at a distance of 2-3 cm) and evenly drive the air stream along all four faces of the smartphone. Pay special attention to the corners, since there is usually the most glue. The process takes from 3 to 5 minutes depending on the power of the equipment.
⚠️ Warning: Never direct a hot jet of air into the center of the back cover or into the camera area for a long time, this can cause the battery to bloat or yellow spots on the matrix.
Once the body is warmed up, quickly but carefully install the suction cup at the bottom of the back, closer to the logo. Pull the suction cup up, creating tension, and simultaneously insert a thin plastic mediator into the resulting gap. Do not use metal blades at this stage, as they can cut through the plume of the fingerprint scanner or damage the glass.
Move the mediator along the side faces, trying not to dive deeper than 3-4 mm. You should feel the glue stretching and moving away. If the resistance is too high, stop moving and add a little more heat. Xiaomi cover should separate smoothly, without the characteristic crack of breaking glass.
Dismantling internal components and access to the battery
When you successfully remove the back cover, you'll see the inside of your smartphone, which is covered by a plastic frame, and it's fixed by a lot of screws of different sizes and lengths, and it's important to sort the screws as they're removed, because screwing a long screw into a short hole can break through the motherboard.
First, you need to disconnect the battery plume from the motherboard, and this is done by the plastic blade after you unscrew the metal protective plate covering the connectors, and only after the power is turned off can you safely continue working with other components, such as the main plume of the display or the camera module.
Replacing the battery, which in the Redmi 9A is glued to the bottom of the case with double-sided tape, will require additional heating. Carefully warm the bottom third of the phone and use a plastic card or spatula to tamper with the battery. Pulling by the wires is strictly forbidden.
| Component | Type of attachment | Tool. | Risks. |
|---|---|---|---|
| Back cover. | Perimeter glue | Suction, mediator. | Broken glass |
| Plastic frame | Screws (different) | Screwdriver PH000 | Carving failure |
| Battery | Double-sided scotch | Plastic spatula | Battery puncture |
| Maternity fee | Screws, plumes. | Tweezers, screwdriver. | The plume break |
When working with the insides of a Xiaomi Redmi 9A smartphone, be careful with the main camera module. It often attaches tightly enough that if you extract it carelessly, you can damage the lens or connector. Use tweezers with wide sponges so you don't put a point pressure on the camera body.
What to do if the battery is blown?
Replace broken glass and repair damage
Often, users don't want to open the lid to replace the battery, but because the back panel itself has broken, and in this case, the dismantling process is the first step to restoring the aesthetic look of the device. The new lid for the Redmi 9A is inexpensive and often sold with adhesive layer applied.
If you plan to use an old lid (for example, when re-painting), you will have to completely remove the residue of the old glue. This is done mechanically with a scalpel and then treated with alcohol. The surface must be perfectly smooth and fat-free, otherwise the new glue will lie unevenly and bubbles will be visible.
- 🧹 Carefully clean the frame of all villi and dust using a soft brush.
- 🧪 Degrease the surface with alcohol or a special cleaner for glass.
- 🧪 Check the integrity of the sealing gum (if it is in your modification).
- 💡 Make sure the speaker and vibrator are sitting tight in their seats.
It's important to check if the glass fragments have damaged the internal components. A fine glass chip can get under the volume buttons or into the charging connector, which will cause functional problems in the future. Blow the insides with compressed air or gently mark out with a brush.
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Save the factory sticker with the IMEI and serial number that is on or below the back cover. When you install a new panel, move this information to avoid losing warranty and device model data.
Assembly of the device and final sealing
The assembly is done in reverse order, but using fresh adhesive. Xiaomi smartphones are best suited to B-7000 or T-7000 series adhesives. They remain elastic after drying, allowing the lid to be reopened without undue effort in the future, unlike superglue, which makes the glass brittle.
Apply a thin, uniform layer of glue to the body frame (not glass!). Avoid getting glue into the speakers, cameras and connectors. Let the glue dry a little (2-3 minutes) to a sticky film state, then carefully align the cover with the body, starting at the top.
Once you dock, press the lid tightly around the perimeter. You can use stationery gums to get better at fixing it, pulling them cross-to-cross over the body, or you can put the phone under a small press (like a stack of books) for 1-2 hours. The glue takes about 24 hours to be fully polymerized.
⚠️ Warning: Do not turn on the phone immediately after assembly if you have been working with a battery or plumes. 10-15 minutes to stabilize the contacts and make sure that the cover is flat without distortions.
The final step will be to check all the functions: touchscreen performance (especially in areas where the disassembly was conducted), button response, camera operation and communication modules, and if everything is working correctly, you can consider the repair successfully completed.
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The quality of repair directly depends on the purity of the gluing surface and the uniformity of the lid press during drying of the glue.
Possible problems and expert advice
Unforeseen situations can occur during disassembly, such as glass can crack even when it is operated carefully if it has microscopic voltage or factory defects, and users often experience the problem of a “falling” touchscreen after assembly, which indicates poor contact of the plume.
If the phone doesn't turn on after assembly, don't panic. Check if the battery is plugged in and the connector is snapped to the end. Sometimes you need to rewire the display plume to reconnect. Be careful: Xiaomi's plumes are very thin and break when you push hard.
Another common problem is getting dust under the glass or display. To avoid this, assemble indoors with minimal dust, you can even slightly moisten the air or wipe the surfaces with a wet wipe (not inside the phone!).