Disassembly Xiaomi Mi9 Lite: a complete analysis of photos, schemes and secrets of the masters

Xiaomi Mi9 Lite

2019

Mi9 Lite

- the task is not simple: here and adhesive back cover, and fragile plumes, and the risk of damage to the fingerprint scanner under the screen.

In this article you will find step-by-step instructions with photos, a list of necessary tools and unique tips from the masters of service centers. We will tell you how to avoid typical mistakes (for example, damage to the flexible battery cable), which parts can be replaced yourself, and when it is better to contact the professionals. Mi9 Lite differs from other Xiaomi models in terms of disassembly – it will save time and nerves.

⚠️ Warning: Disassembling a smartphone will void the warranty (if it is still valid), and incorrect actions can cause permanent damage to the board or screen due to static electricity or mechanical impact. If you are not sure about your skills, entrust the repair to a certified service center.

Preparation for disassembly: tools and security measures

Before you start disassembling the Xiaomi Mi9 Lite, make sure you have everything you need. The lack of even one tool can turn a simple procedure into a nightmare – for example, without a plastic mediator, you risk scratching the body or tearing the plumes.

Here is the minimum set of tools you will need:

Also, prepare your workspace: it should be clean, well-lit and without carpeting (they store static electricity), the ideal option is a table with a rubber mat and a bright desk lamp.

⚠️ Attention: If you understand Mi9 Lite to replace the battery, do not use metal tools to tamper with the battery - this can lead to a short circuit.

Step 1: Removing the back cover – how not to break the fingerprint scanner

The back cover of the Xiaomi Mi9 Lite is glued around the perimeter, and underneath it hides the fragile plume of the fingerprint scanner and antenna contacts. The main mistake of beginners is trying to lid without heating. The glue on the Mi9 Lite is very durable, and without softening you risk damaging the body or internal parts.

Instructions for removing the lid:

1. Turn off your smartphone and remove the tray for SIM-map.
2. Heat the back cover with a hairdryer (60–70°C) for 2-3 minutes, evenly driving around the edges.
3. Suction the lids and carefully pull up.
4. Insert a plastic mediator into the resulting gap and slowly lead it around the perimeter, separating the glue.
5. Be especially careful in the area of the fingerprint scanner (upper part) - here is a plume!

⚠️ Warning: If the lid doesn't lend itself, don't use excessive force, you better warm up the problem area again. Mi9 Lite often occurs when the glue under the fingerprint scanner is held tighter than elsewhere.

After removing the cover, you will see:

• 🔋 Battery with connected plume
• 📡 Antenna contacts on the sides
• 🔄 Fingerprint scanner plume (stick to the cover!)
• 🛠️ 12 screws fixing a metal plate

Important: Some versions of the Mi9 Lite have a fingerprint scanner plume glued to the cover with double-sided tape. Don't tear it off by force - tweez carefully, preheat it with a hairdryer.

Step 2: Shutting down the battery – why do you need to do it first?

Before touching any internal components, be sure to turn off the battery, which will prevent short circuits that could disable the motherboard or other modules. On the Mi9 Lite, the battery connector is located at the bottom and closed with a black protective film.

How to turn off the battery:

1. Remove the protective film from the battery connector (it is glued weakly, you can tamper with a nail).
2. With a plastic blade, gently pull the plume up. Don't use metal!
3. Make sure that the contacts do not come into contact with the body.

⚠️ Attention: If you accidentally touch the battery's plus and minus contacts with tweezers or screwdrivers, it can cause a fire. Mi9 Lite contacts are very close – be careful!

Advice from the master: After disconnecting the battery, wait 1-2 minutes - this will discharge the residual capacitors on the board.

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If the battery is swelling, don't try to puncture it or bend it! This can cause fire. You'd better dispose of it at a special reception center right away.

Step 3: Dismantling the metal plate and motherboard

Under the lid, you'll see a metal plate that covers most components, and it's mounted on 12 different types of screws (PH00, Y00), so remember or photograph their location, which will save time when you build them.

Procedure:

1. Unscrew all the screws and fold them into a container (you can sign the location).
2. Remove the metal plate - it can sit tightly, so put it under the mediator.
3. Now you will see the motherboard, camera, speaker and other modules.

To remove the motherboard, you need to disconnect all the plumes:

• 📸 Main camera plume
• 📞 The plume of the front camera and sensors
• 🔊 Dynamics and microphone plume
• 📶 The antenna module plume

⚠️ Attention: Trails on Mi9 Lite is very fragile. Don't pull them by the wires, just take the plastic connectors and gently scapulate the shoulder blade.

Once all the plumes are turned off, the board should be easily removed. Don't force them if something gets in the way, make sure you've forgotten to disconnect any connector.

Step 4: Replacing the Battery – Why You Shouldn’t Use Metal Tools

The battery on the Xiaomi Mi9 Lite is glued to the body, and replacing it is one of the most difficult procedures. The main danger is damage to the battery with sharp tools, which can lead to electrolyte leakage or even fire.

Step-by-step:

1. Heat the battery with a hair dryer (temperature 50–60°C) for 1-2 minutes.
2. Tap the battery with a plastic spatula on either side and start gently separating.
3. If the glue is too strong, use isopropyl alcohol (a few drops under the battery will help dissolve the glue).
4. After removing the old battery, clean the seat from the glue residue.
5. Install a new battery and glue it to double-sided tape (don’t use superglue!).

⚠️ Warning: If the battery is swelling, do not try to disassemble or puncture it - it is extremely dangerous.

Important: After replacing the battery, be sure to calibrate it:

1. Charge the phone to 100%.
2. Turn off charging and use your smartphone until full discharge (0%).
3. Repeat the charging-discharge cycle 2-3 times.

Step 5: Replacing the screen – How not to damage the fingerprint scanner

The Xiaomi Mi9 Lite screen is one of the most expensive parts to replace. The main difficulty is the fingerprint scanner, which is integrated into the display. If you damage its plume, the touchscreen will work, but unlocking from the fingerprint will become impossible.

Procedure:

1. Turn off the battery (as described in Step 2).
2. Heat the screen with a hair dryer around the perimeter (temperature 60°C).
3. Tap the display with a plastic spatula, starting at the bottom edge.
4. Carefully separate the screen by following the fingerprint scanner plume (it goes to the top of the phone).
5. Disconnect the display and scanner plumes, then install a new screen.

⚠️ Attention: Mi9 The Lite screen is very tightly glued. Don't use metal tools -- they can scratch the glass or damage the matrix.

Tip: Before installing a new screen, check its operability by connecting it to the board. This will help avoid problems after full assembly.

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If the touchscreen doesn’t work after you replace the screen, check to connect the fingerprint scanner plume – often the problem lies in it, not in the display itself.

Frequent Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling the Xiaomi Mi9 Lite, and here are the most common ones and ways to prevent them:

• 🔧 Mixed screws: On board Mi9 Lite uses screws of varying lengths, and if you screw a long screw into an undesignated location, you can damage the board. Solution: photograph the screws before you unscrew them.
• 🔋 Battery plume damage: This plume is very thin and easily torn. Never poke it with metal tools -- just a plastic blade.
• 📡 Break antenna contacts: They are located on the sides of the body and often break off when the lid is not neatly removed. Solution: warm up with a dryer and use a mediator.
• 🔍 Dust falling under the camera: After disassembly, dust particles may remain on the lenses, which will worsen the quality of the photo. Solution: blow the camera with compressed air before assembly.

⚠️ Warning: If the phone doesn't turn on after assembly, don't panic. Check first:

• Is the battery connected?
• Are all the plumes connected to the board?
• Are there any foreign objects (screws, pieces of plastic) left under the payment?

If everything is fine, but the phone is not responding, try connecting it to charge for 10-15 minutes - sometimes this helps to "revive" the device.

FAQ: Answers to Frequent Questions