Replacement of LCD display on Xiaomi Redmi 7A: a detailed guide with nuances

Introduction: when to replace the screen and whether to do it yourself

The Xiaomi Redmi 7A screen is one of the most vulnerable parts of a smartphone. Cracks, broken pixels, a broken touchscreen or a flickering backlight often cause replacement displays. But before you take on a soldering iron and a screwdriver, it is important to assess the scale of the problem and your strength. In 80% of cases, screen damage is mechanical: falling on asphalt, hitting a hard surface or hitting a pressure in your pocket. Less often, factory defects (such as a plume detachment) or moisture.

Self-replacement of the LCD display on the Redmi 7A will cost 2-3 times cheaper than in the service center, but will require care and patience. The average cost of the original module (including touchscreen and frame) is from 1,500 to 2,500 rubles, depending on the supplier. Non-original Chinese counterparts can be found for 800-1,200 rubles, but they often sin poor color reproduction and short service life. If you have never disassembled smartphones, it is better to train on an old device or enlist the support of an experienced friend.

This instruction will be suitable for the Redmi 7A with the M1903C3GG (global version) and M1903C3GG (China) and make sure that your device meets these parameters - the design of the screen in other versions (for example, Redmi 7 or Redmi 8A) may be different!

Preparation: tools and spare parts

Before you disassemble, you'll have to assemble a complete set of tools, and without the right tools, you'll risk damaging the plumes, tearing off the contacts, or scratching a new matrix.

• 🔧 Plastic mediators (2-3 pieces) - for careful liding and disconnection of adhesive joints.
• ⚒️ The screwdriver (PH00 or PH0) — The magnetic tip will make it easier to do the job.
• 🔥 A hair dryer or a thermo-air station to soften the glue under the screen. Optimal temperature: 60-80°C.
• 🧲 Magnetic mat or tray – so as not to lose small screws and details.
• 📱 New LCD module – check compatibility with your model (original or quality analogue from Tianma or BOE).
• 🧴 Isopropyl alcohol (90%+) — Cleaning contacts and removing glue residues.
• 🎚️ Suction - will help to raise the screen after heating.

Warning about glue: in Redmi 7A, the screen is glued around the perimeter with 3M double-sided high-strength tape. If you try to tear it off without heating, you are almost guaranteed to tear the plumes or damage the glass. Use the hair dryer at minimum power, holding it at a distance of 5-7 cm from the body, so as not to overheat the battery.

Disassembly of the phone: remove the back cover and battery

Start by turning off your phone and retrieving it. SIM-I'll take the cards and the memory cards:

1. Heat the back cover with a hair dryer around the perimeter for 1-2 minutes. This will soften the glue under the lid.
2. Insert a plastic mediator into the gap between the lid and the body (start at the bottom edge where the charging connector is). Carefully drive the tool along the edge, separating the latches.
3. Remove the lid, which is held on 8-10 plastic clips. Don't put too much effort into breaking them.
4. Unscrew 10 screws that fix the metal plate above the battery (use a cross screwdriver).
5. Disconnect the battery plume with a mediator. It's attached to a JST 1.0 connector -- put it on the side, not pull it on the wires!

Critical detail: In the Redmi 7A, the battery plume is soldered to the board via a fuse, and if you accidentally close the contacts with a metal tool, it can disable the power controller, and always use plastic or wooden tools when working with the battery.

Disconnecting the old display: working with plumes

Once you take off the battery, you'll have access to the motherboard and the display plumes, and in Redmi 7A, the screen is connected through two plumes:

• The main plume (LCD + Touch) transmits the image and sensor data.
• The backlight plume controls the brightness of the screen.

To disconnect them:

1. Carefully put a black lock on the connector of the main plume (it opens as a lid).
2. Remove the plume by pulling it parallel to the board, not up!
3. Repeat the action for the backlight plume (it is thinner and shorter).
4. Warm up the screen with a hair dryer again (30-40 seconds) and with the help of a suction cup lift it from one edge.

If the screen doesn't respond, don't try to pull it off by force. The glue probably hasn't softened enough. Reheat it by paying special attention to the corners, where the tape usually holds tighter. At the very least, you can use a thin guitar string or a special thread to cut the glue, but it takes experience.

Installation of a new display: nuances of connection

Before installing a new screen, check it for performance, temporarily connect the plumes to the board (without fixing the connector cover) and turn on the phone. If there is an image but the colors are distorted or there are vertical stripes, the problem may be:

• 🔌 Bad contact – check if the plume is tightly inserted.
• 🔥 Overheating matrix - let it cool for 5-10 minutes.
• 🛠️ Marriage module – if defects remain, return the screen to the seller.

If the test was successful,

1. Apply a thin layer of double-sided tape (such as Tesa 61395) around the perimeter of the new screen. Avoid excess glue - it can squeeze out and interfere with assembly.
2. Carefully apply the screen to the body, combining the holes for the speaker and the front camera.
3. Set the slacks in the slacks and lock the black latches.
4. Do the final test: check the sensor (swipe your finger across the screen), brightness and color reproduction.

Important for the touchscreen: after changing the screen, you may need to calibrate the sensor. Go to Settings → System → Additional → Screen Calibration and follow the instructions. If this is not available, install the Touchscreen Calibration application from Google Play.

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If the screen becomes less sensitive after assembly, try removing the protective film from the inside of the glass (if any), sometimes the manufacturers glue it to protect during transportation, but it worsens the touchscreen.

Phone assembly and final checks

The assembly is done in reverse order, but there are a few critical points:

1. Battery: Before you plug in the plume, make sure it's free of contamination.
2. Screw them cross-twisted to avoid skewing the plate. Don't tug - the thread in the Redmi 7A is pretty soft.
3. Back cover: Start snapping it from the top edge (where the camera is), then gradually press it around the perimeter. If the cover doesn't sit tight, check if the plume or dust is disturbing.

After assembly, turn on the phone and perform checks:

If you find problems, take the phone apart again and check:

• 🔌 Fluid density.
• 🔋 Battery contacts (sometimes oxidation causes screen flickering).
• 🛠️ Integrity of flexible printed circuit boards (no cracks).

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If the phone stops turning on after you change the screen, check the battery plume connection, and 90 percent of the time, the problem is with the battery plume, not the new display.

Frequent Mistakes and How to Avoid Them

Even experienced wizards sometimes make mistakes when replacing the screen with a Redmi 7A. Here are the most common ones and ways to prevent them:

⚠️ Attention: if you accidentally rip the backlight plume, the screen will work, but with a very dim picture. Don't confuse this with a matrix malfunction! The backlight plume can be replaced separately (article: XM-7A-BL-01).

• 🔥 Battery overheating - keep the hair dryer at a distance and don't direct hot air directly to the battery.
• 🧲 Loss of screws at Redmi 7A 3 screw types are used (length 3 mm, 4 mm and 5 mm) If you confuse them, you risk damaging the board.
• 📱 Dust ingress - even small particles under the screen will be visible when turned on.Work in a clean room and use an antistatic mat.
• 🔌 The plume hall - never bend them at right angles. The plumes should bend smoothly, with a radius of at least 5 mm.

Another common problem is the moire effect after the screen is replaced, which is a wavy pattern when you scroll through the light pages, usually because the matrix is incompatible (for example, if you installed a Redmi 6A screen instead of a 7A screen), and the solution is to replace it with the original part.

FAQ: Answers to popular questions