Replacement of the screen on Xiaomi Redmi Note 9: a complete guide from disassembly to assembly

A cracked or broken screen on the Xiaomi Redmi Note 9 is one of the most common problems faced by owners of this smartphone. The reasons can be different: a fall from a height, a strong blow, a factory defect, or even a banal moisture hit under the glass. In most cases, the screen is subject to replacement, but it does not always require contacting a service center. If you have basic skills with technology and patience, you can cope with the task yourself - saving from 3,000 to 8,000 rubles (this is how much they charge for replacing in the workshops).

But before you start to use the tools, it's important to assess the extent of the damage. For example, if you have colored bars on the screen, but the sensor responds to touch, the problem may not be in the display itself, but in the plume or motherboard. But a black screen with backlight (when the image is not visible, but the backlight is working) most often indicates damage to the matrix. In this article, we'll learn how to correctly diagnose the malfunction, select a quality screen, and finally replace it without risking damage to other components of the smartphone.

If you've never taken a smartphone apart before, don't rush to buy parts. First, check out the manual, assess your strength and decide if you're ready for the challenges ahead. For example, battery detachment is one of the most critical phases where many newcomers make mistakes. But don't worry, we'll detail each step, give tips on how to choose tools, and tell you how to avoid typical problems.

By the way, if your Redmi Note 9 is still warranty, self-repair will automatically cancel it. In this case, it is better to contact the official Xiaomi service - even if the repair is paid, you will retain a warranty for other components.

1. Diagnostics of the problem: do you really need a new screen?

Before you order a new display module, make sure that it's the one that's the problem, and sometimes the symptoms that seem "screen-like" are actually related to other components, and here are the main signs that will help you identify the malfunction:

✅ Cracks or chips on glass are the most obvious case. If the damage is only external (the glass is cracked, but the image and sensor work), you can do with replacing the glass, but it is more difficult and expensive than replacing the entire module. On the Redmi Note 9, the glass is glued to the matrix, so more often they change everything together.

✅ Black screen, but the phone is on (sounds, vibrations, backlights are there) This can be both a matrix damage, a plume problem or even a motherboard problem. To check, connect your smartphone to your computer or TV through a computer or TV. USB-C → HDMI If there's an image, it's the screen or the screen connection.

✅ Colored stripes, artifacts, flickering, most often it's a sign of damage to a matrix or graphics chip, if the stripes appear after a fall, most likely a screen, if for no apparent reason, maybe a problem is in the firmware (try resetting) or in the motherboard.

✅ The sensor is not responding or it's partially working, and there are two options: the touchscreen is damaged, or the plume has gone away. Sometimes it helps to reconnect the plume, but more often it requires a replacement module.

If you are not sure about the diagnosis, try connecting your smartphone to your PC and checking it through the Mi program. PC suite ADB. For example, the team:

adb shell dumpsys window displays

It will show the current state of the display. If the answer is mDisplayState=OFF, But the phone is on -- the problem is exactly the screen or the connection.

2. Selecting a new screen: original vs. copy, which is better?

The quality of the spare part is not only the look of the car, but also the durability of the repair. There are three main types of screens on the market for the Redmi Note 9:

• 🔹 Original (OEM) — removed from other smartphones or manufactured at the Xiaomi factory. The highest quality, but also the price is appropriate (from 5 000 to 7 000 rubles.
• 🔹 Premium copies are made in the same factories as the originals, but without the Xiaomi logo. OEM, a lower price (from 3,500 to 5 000 rubles) Often sold under brands JK, DX, TFT.
• 🔹 Budget copies are cheap screens (from **2,000 to 3,000 rubles)), but with the risk of poor color reproduction, uneven illumination or quick failure.

When choosing, pay attention to the following parameters:

• 📏 Screen model. Redmi Note 9 (codename merlin) is suitable for modules with a marking JD9365 or JD9366 (Please specify your model in the settings (Settings) → The phone. → Model).
• 🔧 Some screens are sold with a pre-painted frame, which makes it easier to install. Others require the frame to be moved from the old screen, which is more difficult.
• 🎨 Color rendering: Original screens have more natural colors, whereas cheap copies can give a cold or warm hue.
• 🔋 Sensor, make sure you have a touchscreen that supports all gestures. MIUI (For example, Double Tap to Wake).

Where to buy? There are reliable options.

• 🛒 AliExpress is a great choice, but a long wait (2-4 Look for sellers with higher ratings 98% and Russian reviews.
• 🛒 Yandex Market / Ozon - fast delivery, but prices are higher. Check that the description says "100% testing before shipping".
• 🛒 Local service centers -- sometimes they sell parts in bulk, and you can save money, but you're more likely to run into a used screen.

💡

Before you buy, ask the seller to send a video with a screen test (checking the backlight, sensor and color), which will reduce the risk of getting a defective part.

3. Tools required: what will be needed to replace

To replace the screen with the Redmi Note 9, you'll need a dedicated tool, and don't try to get by with the tools you need, which is almost guaranteed to damage the body or internal components.

We also recommend that you prepare:

• 📱 Spare phone in case something goes wrong and you need to contact the master immediately.
• 📸 Camera or smartphone – to photograph the disassembly process (this will help not to confuse screws and plumes during assembly).
• 🧻 Soft fabric or wipes – to clean the screen and case from fingerprints.

Important: the screws in the Redmi Note 9 are different lengths, and if you confuse them when you build them, you risk damaging the motherboard or the battery, and you'd better put them in order on a piece of paper with notes.

4. Step-by-step instructions: how to disassemble a smartphone and replace the screen

Now, to the most critical stage, follow the instructions carefully and take your time — 1,5-2 hourly, for experienced craftsmen — 30-40 minute.

Before starting work:

1. Turn off the phone and remove it. SIM-memory-card.
2. Charge the battery on. 30-50% — This will prevent accidental switching on during repairs.
3. Work on a clean, well-lit table without carpets (so you don’t lose small details).

Turn off the phone and remove the cards|Charge the battery on 30-50%|Prepare tools and workplace|Take a picture of the original state of the phone|Wear an antistatic bracelet (optional)-->

Step 1: Removing the back cover

The back cover of the Redmi Note 9 It is glued, so it needs to be carefully tampered with after heating. Use a dryer at minimum power (or a thermo-air station when you heat it up). 60°C) and warm up the edges of the shell during 2-3 minute.

Next:

1. Insert a plastic mediator into the gap between the lid and the case (start at the bottom edge where the charging connector is).
2. Carefully drive the mediator around the perimeter, separating the lid. Do not force - if the lid does not respond, warm up again.
3. When you remove the lid, put it aside, and be careful, there are fingerprint scanner plumes and antenna contacts underneath.

Step 2: Shutting off the battery

This is the most dangerous stage! The battery in the Redmi Note 9 is glued to the body and needs to be carefully separated to avoid damaging.Use a plastic mediator and isopropyl alcohol to soften the glue.

Procedure:

1. Unscrew the screws that fix the metal plate over the battery (usually 4 screws) T3).
2. Carefully slap the plate and put it aside.
3. Unplug the battery plume with a plastic mediator (do not use metal tools!).
4. Apply a few drops of isopropyl alcohol under the battery and wait 1-2 minutes to soften the glue.
5. With a mediator, gently tuck the battery, starting at the top edge. Don't pull it by the wires!

Step 3: Disconnect the screen plumes

Once you take off the battery, you'll see the motherboard and the plumes coming to the screen, and you'll have to detach them in the following order:

1. Unscrew the screws fixing the metal plate over the plumes (usually 2 screws) T3).
2. Carefully pluck the plate and remove it.
3. With a plastic mediator, disconnect: 🔌 Display plume (wide, usually left). 🔌 The touchscreen plume (already on the right). 🔌 Fingerprint scanner plume (if any).

Be very careful: the plumes are very fragile! If you damage the contacts, the new screen may not work.

Step 4: Remove the Old Screen

Now you can take the old screen. It's glued around the perimeter, so:

1. Warm up the screen edge hair dryer (temperature) 70-80°C, 2-3 minute).
2. With a suction cup, gently raise the screen (start at the bottom edge).
3. Take the mediator and walk around the perimeter, and you'll take your time, and if the screen doesn't respond, warm it up again.
4. After removing the screen, clean the frame of the glue residues with isopropyl alcohol.

Next:

1. Carefully place the new screen on the frame and align it around the edges.
2. If the kit is bilateral tape, stick it around the perimeter of the frame, then press the screen.
3. If there is no tape, apply a thin layer of glue B-7000 edges and press the screen on 1-2 minute.
4. Connect the plumes in reverse order (first touchscreen, then display, then fingerprint scanner).
5. Secure the metal plate and twist the screws.

Step 6: Build the phone

Collect the phone in reverse order:

1. Install the battery and connect its plume.
2. Hold the metal plate over the battery.
3. Install the back cover, having previously cleaned it of dust.
4. Warm up the edges of the lid with a hair dryer (60°C) and press it on 1-2 minutes.

After assembly, turn on the phone and check:

• 📱 Does the display work (are there broken pixels, stripes).
• 👆 Does the sensor respond to touch.
• 🔋 Does the phone charge (sometimes after repair you need to reconnect the charging plume).

💡

If the screen doesn't turn on or the sensor doesn't work, don't panic. 90 percent of the time, the problem is with the plumes that aren't tightly connected. Take the phone apart again and check all the contacts.

5. Common Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when changing screens, and here are the most common problems and ways to prevent them:

• 🔥 Train damage. Most often it is due to the use of metal tools. Always use plastic mediators! If the plume does break, it can be replaced separately (cost). 500-1500 ruble).
• 🔋 Battery problems. If the phone doesn't turn on after assembly, check if the battery plume is connected. Also make sure the contacts aren't contaminated (wipe them with alcohol).
• 📵 If the signal is missing after the repair, you probably forgot to connect the antenna plumes (they go from the back cover to the motherboard).
• 🎨 Poor color reproduction. If the colors on the new screen are too cold or warm, check the display settings (Settings) → Screen. → If it doesn't work, you may have bought a low-quality copy.
• 🔌 The charging is not working. Check if the charging plume is bent when you assemble it. Also clean the connector from dust and debris.

If the screen is working after replacing but new problems have appeared (such as spontaneous taps or flickers), try resetting (Settings) → Additionally. → Recovery and reset. Sometimes this helps to "reset" the display drivers.

💡

If the screen becomes less sensitive after the replacement, check if the protective film is installed correctly (if it comes with a set), sometimes it worsens the reaction to touch.

6. When is the best time to contact the service?

While replacing the screen with the Redmi Note 9 is a doable task, there are situations where it is better to trust the professionals:

• 🛠️ You've never taken out a smartphone. The risk of damaging the motherboard or the plumes is too high.
• 🔥 The battery is swollen or deformed. It's dangerous - it's better not to risk it.
• 💻 Once replaced, the screen doesn't work and you can't find the cause.A wizard with the equipment will diagnose the problem faster.
• 📱 Phone warranty.Self-repair voids Xiaomi warranty.
• 💰 You're not sure about the quality of the screen you bought.

The cost of replacing the screen in the service:

• 📍 Official service Xiaomi: 5 000 – 8 000 rubles (with spare parts).

If you do decide to use the service, choose a workshop with good reviews and a guarantee for work. Ask to show the screen before installing it, so you will make sure that it is free of defects.

7. How do you extend the life of a new screen?

To keep the new screen as long as possible, follow these tips:

• 🚫 Avoid extreme temperatures: Do not leave your phone in the sun (like on a torpedo in a car) or use it in the cold below. -10°C. This may cause adhesive detachment or damage to the matrix.

We also recommend turning off automatic brightness control (Settings). → Screen. → Autobrightness) and set a comfortable value manually. Frequent brightness changes shorten the life of the backlight.

💡

If you drop your phone frequently, consider buying a case with shock-absorbing corners (like the Spigen Tough Armor or the Spigen Tough Armor). UAG Plasma: They cost more than normal, but they significantly reduce the risk of screen damage when you fall.

FAQ: Frequently Asked Questions