Replacing a broken or faulty display with a Xiaomi Mi A3 is a procedure that requires not only accuracy but also understanding the architecture of modern smartphones. The device is built on the Android One platform, which implies a minimalist design, but does not simplify the repair process. The main difficulty lies in the In-Display Fingerprint technology, which requires the perfect fit of the fingerprint scanner to the new screen.
If you damage a glass or a matrix, you have to choose between replacing only the glass (which is only possible in a pressed workshop) or completely replacing the module assembled. At home, the most realistic and safe option is to install a new OLED module, which ensures that the brightness, color reproduction and, critically, the performance of the fingerprint scanner is maintained.
Before starting work, it is important to understand the risks: poor-quality assembly can lead to dust and damage to the plume - to the complete inoperability of the touchscreen. glue B-7000 or T-7000 is a prerequisite for sealing the case, as the factory moisture protection at the opening is lost irrevocably. Carefully study the sequence of actions to avoid fatal errors during dismantling.
Tools and workplace preparation required
The quality of the repair depends on the preparation. You do not need industrial equipment, but a set of specialized tools is mandatory. The use of improvised tools, such as a knife or needle, is strictly prohibited, as this will damage the internal components or short circuit.
Pay special attention to the organization of lighting. You will have to work with small parts and connectors that are not visible in dim light. Also make sure you have a screw folding capacity, since the Xiaomi Mi A3 uses screws of different lengths, and their entanglement can be critical.
- 🔧 Screwdriver kit: Phillips cross #00 and silk for opening.
The workplace must be clean and dry.Static electricity can damage electronics, so it is recommended to use an antistatic bracelet or periodically touch a grounded metal object.Be sure to turn off your smartphone and remove the tray before starting disassembly. SIM-map.
Removal of the back cover and removal of protective elements
The process of disassembling the Xiaomi Mi A3 begins with a glass back panel that is glued around the perimeter and requires heating to remove it. Don't try to uncook the lid with a cold tool - the glass will burst, and the fragments may injure you or damage the internal plumes.
Warm up the perimeter of the back cover evenly for 2-3 minutes. Then insert the suction cup at the bottom and gently pull to create a gap. Insert a thin plastic blade into the resulting gap and run it along the edges, cutting the glue layer. Move slowly, without dipping the tool deep, so as not to touch the battery.
⚠️ Attention: The back window is very fragile, and when you heat it up, it becomes even more vulnerable. If the lid cracks, it can be temporarily locked.--WIDGET:checklist:Check before assembly: Check the touch screen|Make sure there is no dust under the screen|Check the fingerprint scanner.|Check the sound of the speakers|Check the cameras.--> When you remove the back cover, you'll see the inside of the smartphone, and the first thing you need to do is turn off the battery, which is a critical safety step. Any manipulation of the cables of the display or motherboard under voltage can cause the power controller to burn, carefully unscrew the screws that lock the protective plastic bar in the center of the case, and underneath it are the main connectors. Use a plastic spatula to turn off the battery plume. Only then can you begin removing other components that interfere with screen access. Full access to the display often requires the removal of the main motherboard or its significant displacement. A3 The board is mounted with multiple screws and connected by plumes to the lower board (where the charging connector is located). NFC, which is often located on the back cover or the top of the body. 🔋 Disconnect the battery connector first. 📷 Carefully disable the main camera plume. 📡 Remove the module. NFC, if it interferes with access to the screen plume. 🔌 Disconnect the antenna cable (coaxial wire) if it passes over the board. Don't pull the plume wires themselves. All connectors have latches or just sit tightly in the connectors. The movements should be straight upwards, without skewing. If the connector doesn't go, check if you forgot to unscrew the pinch plate. What to do if the plume breaks? If you damage the plume during dismantling, it can't be restored at home. You'll need to buy a new plume or replace the entire node to which it belongs. Solding such thin contacts requires a microscope and experience. Replacing the display module and transferring components from the old broken screen to the new one. In the Xiaomi Mi A3, you can place a speaker, a vibrating motor and sometimes a deck on a femotor and a deckleteer, and it is also held neatably on a sidebar. When you install a new screen, make sure that all of these elements fall into place tightly, without gaps, or there will be rattles when you work. Pay special attention to the fingerprint scanner. In this model, it is integrated into the display. When you install the new module, make sure that the optical sensor (if it comes with a screen) or the area under the scanner is clean. Fat spots or dust will cause the unlock to stop working. Component mounting Risk Clay/Scotch High (membrane) Action Gret (Steep) and finally connect the plugging the device to the mainframe. Turn on your smartphone and check the basic functionality: image, touchscreen operation in all zones and, most importantly, the fingerprint scanner response. 💡Before final assembly, wipe the inside of the new screen and the body frame with an alcohol napkin. OLED-The matrix will look like a bright broken pixel. The slurry of the body and the final assembly If the test is successful, you can proceed to the final assembly. B-7000 or T-7000 You can put it on the frame of the new display and around the perimeter of the smartphone body, and don't put too much glue on it, because it can squeeze out and stain the matrix or the plumes, connect the halves of the case and press them tightly together, make sure there are no gaps. For better adhesion, use special rubber harnesses or stationery gums, wrapping your smartphone around the perimeter on the 15-20 minute. This will ensure that the pressure is evenly distributed. Once the glue is dry (complete polymerization takes about 24 hours, but the initial grip takes 30 minutes), you can install a back cover, and you also need to apply a fresh layer of glue on it. When installing the cover, make sure that you do not damage the plume. NFC, which is often glued to the inside of the glass. ⚠️ Warning: Don't turn on your smartphone right after assembly if you've used a lot of glue. The adhesive pairs can condense on the camera optics or sensors. Let the device stand in a ventilated place. Calibration and health check After assembly, it may be necessary to calibrate the touch screen, especially if you notice minor biases or "dead zones." Android One doesn’t have a built-in calibration engineering menu available to the user, but you can use standard diagnostic tools. To check, use the built-in test menu. Type ##6484## into the dialer. This will open the engineering menu. CIT. Select "Touchpanel" and run a line drawing test. All lines must be continuous, without tears. Also check the multi-touch. Xiaomi Mi screen A3 It supports up to 10 simultaneous touches, and if the multi-touch test shows fewer dots or dots, it may be that the plume is not fully connected or the screen is defective. 🖐 Conduct a test on drawing lines in the engineering menu. 👆 Check multi-touch (up to 10 points). 💡 Evaluate the uniformity of the lighting and the absence of color spots. 🔊 Make sure the speaker is clear (no wheezing). If all tests are successful, congratulations, you've successfully replaced the screen. If you have sensitivity issues, try reinstalling the plume by turning off the battery beforehand. 💡The quality of the adhesive and the purity of the assembly is 90% of the success, and the dust inside the case or the poor sealing will negate all efforts to replace the expensive one. OLED-Why does the fingerprint scanner not work after the screen is replaced? A3 It reads the image of the finger through the holes in the matrix, if the screen is unoriginal, low quality or poorly pressed, the light does not pass correctly, and the cause may be due to contamination of the scanner area with glue or a software failure that requires resetting. Can you just replace glass without a matrix? Theoretically, yes, but it's not possible at home. It requires a separator (to separate the glass and matrix with liquid nitrogen or heating) and a laminator (to stick new glass under vacuum). OLED The risk of damage to the matrix when the glass is separated is more than 80%. B-7000? Primary grip takes 3-5 minutes, allowing the details to be fixed with harnesses. It takes about 1-2 hours to dry completely to the point where you can actively use your smartphone. Full polymerization and maximum strength gain occur within 24 hours.