How to disassemble Xiaomi Mi 9 yourself: detailed instructions with photos and nuances

Xiaomi Mi 9 is the flagship of 2019, which is still popular among users due to its powerful hardware and affordable price in the secondary market. However, over time, even such reliable devices require repairs, from replacing the battery to cleaning the connectors or recovering from a fall. Disassembling a smartphone is not an easy task, especially if you are doing it for the first time. In this article, we will explain how to disassemble the Mi 9 without damage, what tools you will need and what to look for to avoid turning the repair into an expensive mistake.

It's important to understand that disassembling your smartphone takes away your warranty (if it's still in effect) and can cause permanent damage if you act carelessly. If you're not sure about yourself, you better call a professional, but if you decide to act on your own, follow our instructions Step-by-step.

We’ll look at two scenarios: partial disassembly (for example, to replace the battery or SIM card) and complete disassembly (for access to the motherboard or cameras), and how to avoid the typical mistakes that beginners make, and what to do if something goes wrong.

Preparation for disassembly: tools and security measures

Before you start disassembling the Xiaomi Mi 9, make sure you have everything you need. Lack of the right tools is the main cause of damage to the body or internal components.

• 🔧 Set of screwdrivers (cross-haul) PH00, flat 1.5 mm, five-pointed Y00 back-coat).
• 📱 Plastic mediators or shoulder blades (for careful slashing of the cover and connectors).
• 🔥 Dryer or thermo-air station (to soften the glue under the back panel).
• 🧲 Magnetic mat or organizer (so as not to lose screws and small details).
• 🔋 Suction cup (helps to lift the back cover after heating).
• 🛡️ Antistatic bracelet (protection against static electricity that can damage the motherboard).

Also, prepare your workspace: it should be well lit, clean and spacious. Work on a flat-surfaced table to avoid falling parts. If you don't have an antistatic bracelet, touch a grounded metal object (such as a heating battery) with your hand before starting work to relieve static charge.

⚠️ Warning: Don't use metal tools to tuck in plastic latches! This causes chips and cracks on the body. Plastic mediators or guitar mediators are better.

If you are planning to replace the battery, pre-order an original or high-quality analog battery with a capacity of at least 3300 mAh (the original capacity of the Mi 9). Cheap fakes can swell or fail in a few months.

Step 1: Turn off and remove the back cover

The first and most important step is to remove the back panel. In the Xiaomi Mi 9, it's glued around the perimeter, so you don't just rip it off. Here's how to do it right:

1. Turn off your smartphone and remove the tray for SIM-cards (use a paper clip or special key).
2. Heat the back cover with a hair dryer for 2-3 minutes, keeping it at a distance of 5-7 cm The temperature should be 60-80 ° C - do not overheat so as not to damage the display!
3. With a suction cup, lift the lid at the bottom edge (near the USB-C connector). If it doesn't respond, repeat the heating.
4. Put a plastic mediator into the gap and gently swipe it around the perimeter, separating the glue. Be careful around the volume and power buttons - there are plumes!

If the lid doesn't lend itself, don't use too much force. You better warm up the problem areas again. In Mi 9, the glue is applied unevenly, so some areas may require more heat.

⚠️ Warning: Do not use a knife or screwdriver to lid the lid! The risk of damaging the fingerprint plume or antenna contacts is extremely high.

Once the lid is removed, you will see the battery, motherboard and cameras. Take your time to disconnect the battery immediately - first inspect the insides for damage or corrosion (especially if the phone fell into the water).

Step 2: Disconnect the battery and remove the motherboard

Before touching any internal components, be sure to turn off the battery.This will prevent short circuit and damage to the board. In the Mi 9, the battery connector is located at the top of the device (near the cameras).

Carefully put a plastic blade on the connector and disconnect it. If the connector is stuck, don't pull it, just sway it from side to side. After the battery is turned off, wait 1-2 minutes for the residual capacitors to run out.

Now we can start to extract the motherboard.

1. Unscrew all the screws holding the board (there are about 10-12 pieces, of different sizes – remember where it was!).
2. Disconnect all the plumes: the display, the cameras, the speaker, the buttons and the fingerprint sensor. In the Mi 9, they are fixed with latches - lift them carefully without breaking.
3. Raise the charge with a mediator. If it doesn't come out, check if all screws are unscrewed (often forgetting the screw under the sticker!).

The Mi 9 motherboard is quite fragile – avoid bending and pressure on the chips. If you are disassembling a phone to repair the board (for example, after getting moisture), immediately inspect it for oxidation or burnt elements.

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If the screws don't unscrew, drop some WD-40 or alcohol on them and wait 5 minutes. Don't use force - the plucked slats will complicate the assembly!

Step 3: Replacing the battery – nuances and errors

The battery in the Xiaomi Mi 9 is one of the most vulnerable parts, and over time it loses capacity, it swells up, it stops holding charge, and replacing the battery is the most common reason for disassembling this smartphone. Here's how to do it right:

When you turn off the battery connector, you have to remove the old battery pack, and it's glued to the body, so:

1. Put a plastic blade on the battery from any edge and pull it up. If it doesn't lend itself, heat the battery with a hairdryer (but don't overheat!).
2. There may be two pulling bands (black) under the battery - pull behind them to separate the glue.
3. Remove the glue residue from the body with alcohol or acetone. The new battery should lie flat, without distortion.

When installing a new battery:

• 🔋 Use bilateral tape or special glue to fix.
• 🔌 Connect the battery connector last, after assembly of all other components.
• ⚡ The first switch on after the replacement can take up to 5-10 minutes – this is normal.

⚠️ Warning: If the new battery is quickly discharged or the phone is not turned on, check the polarity of the connection and the integrity of the charging plume. Often, when replacing the battery, the connector on the board is damaged.

Step 4: Disassembling cameras and speakers

The Xiaomi Mi 9 triple camera (48 MP + 12 MP + 16 MP) is one of the most difficult parts to disassemble. If you need to replace the camera glass, clean the lens or repair the plume, act extremely carefully.

To remove the camera module:

1. Unscrew two PH00 screws holding the metal plate over the cameras.
2. Carefully disconnect the plume (it is very thin and easily torn!).
3. Put a plastic blade on the camera module and remove it.

The speakers in the Mi 9 are located at the bottom of the body to replace them:

• 🔊 Unscrew the screws holding the metal lattice.
• 🛠️ Disconnect the speaker connector from the motherboard.
• 🧹 Before installing a new speaker, clean the hole from dust - this will improve the sound.

In the Mi 9, the top speaker is both conversational and multimedia, so when you replace it, check the sound in both modes.

Step 5: Building a Phone – How Not to Make Mistakes

Building the Xiaomi Mi 9 after disassembly is as important as disassembling, and many users face problems like a broken display or a lack of network due to improperly connected plumes.

• 🔧 Rotate the screws in reverse order using a magnetic organizer!
• 🔌 Connect the plumes to fix the board - it is more convenient to check the density of the contact.
• 📱 Stick the back cover to a new double-sided scotch (for example, 3M 9448A).
• 🔋 Connect the battery last after checking all other components.

After assembly:

1. Turn on your phone and check the sensor, cameras, sound and network.
2. If something doesn't work, take the phone apart again and check the plumes' connection.
3. Charge the battery to 100% and discharge to 0% 2-3 times to calibrate the new battery.

⚠️ Warning: If the phone doesn't turn on after assembly, but when you connect to charging, it shows an indication, the problem may be the power button or its plume.

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The most common build error is the wrong connection of the display plume. If the screen is not working, but the phone vibrates when turned on, check the connector on the board and the plume itself for damage.

Typical problems after disassembly and their solution

Even if you followed the instructions, after disassembling the Xiaomi Mi 9, you may have problems, and here are the most common ones and ways to fix them:

If the phone overheats after disassembly, this may indicate:

• 🔥 Poor heat sink (check the heat paste on the processor).
• 🔋 Battery defect (blown or poor quality).
• 🛠️ Short circuit on the board (multimeter diagnostics required).

In most cases, the problem is solved by re-disassembling and checking the connections, and if the fault persists, the components of the board may be damaged and professional repairs will be required.

FAQ: Frequent questions about the dismantling of Xiaomi Mi 9