How to open Xiaomi Mi 9: disassembling the case for repair or upgrade

Xiaomi Mi 9 is the flagship of 2019, which is still popular due to its powerful hardware and affordable price in the secondary market. However, over time, even this smartphone has typical problems: battery drains, the screen cracks or the speaker fails. To replace a part yourself or conduct a diagnosis, you need to open the case correctly — and this is not as easy as it seems.

The body of the Mi 9 is glued around the perimeter, and inside are hidden fragile plumes and a battery that can swell over time. Disassembly errors often lead to damage to the display, a break in contacts or even a short circuit. In this article, unique disassembly schemes tailored to the features of this particular model, a list of necessary tools and step-by-step photos with the comments of the masters.

Preparation for disassembly: what you need to know before the beginning

Before you start screwdriver, consider your strengths and risks. Xiaomi Mi 9 is not the most difficult to disassemble smartphone, but also not the easiest.

• 🔧 The warranty is voided whenever you open the case, and if the phone is warranty, you should contact the service center.
• 🔋 The battery can be bloated. If the case is deformed or the screen "steps away" from the frame, this is a sign of danger.
• 📱 The display and back cover are glued together with double-sided tape and glue B-7000. Heat will be required for a safe room.
• 🛠️ You need tools, a screwdriver and a knife won't work, and you can damage the plastic latches.

If you've never taken a smartphone apart before, practice on an old device or watch video guides. For example, there are detailed videos on YouTube from JerryRigEverything or RepairLabs channels showing the process of disassembling the Mi 9 with pitfall commentary.

Tools required: full checklist

Without the right disassembly tools, the Xiaomi Mi 9 turns into a lottery.

Plastic mediators (2-3 piece.)|Screen suction cup (∅ 50-60 mm)|Fryer-dryer|Screwdriver. T3 and T5 (screw)|Tweezers with curved ends|glue-cutting knife|Gloves (optional)|Loupe or magnifying glass-->

Where can I buy tools?

• 🛒 Repair kits are sold on AliExpress (search for “Xiaomi repair tool kit”) or in radio stores.
• 🔥 The hair dryer should have temperature adjustment - optimally 60-80°C. Household hair dryer is not suitable for hair dryer!
• 🧲 The magnetic mat will help you keep your screws safe, and you can replace it with a piece of paper and tape.

The cost of a full set is 500 to 1,500 rubles. If you plan to disassemble smartphones regularly, the investment will pay off. For a one-time replacement of the battery, you can do with a minimum set: a sucker, a mediator and a screwdriver.

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Before disassembling, take a picture of the location of all the screws and plumes on the phone - this will help to collect it back without errors.

Method 1: Classic disassembly with heating (to replace the battery or screen)

This method is suitable for most tasks: battery replacement, display, speaker or camera, the main thing is to take your time and follow the instructions.

Step 1: Turn off and prepare the phone

Turn off the Mi 9 completely (press the power button and select "Switch off"). SIM-Don't take the battery out until the plumes are completely shut down.

Step 2: Heating the body

Turn on the dryer at 70-80°C and warm up the edges of the screen evenly for 2-3 minutes. Keep the dryer at a distance of 5-7 cm so as not to overheat the display. The goal is to soften the glue, but not melt the plastic!

Step 3: Screen separation

Stick the suction cup to the bottom of the screen (above the Home button) and pull up. At the same time, insert a plastic mediator into the gap that appears. Don't use metal tools - they will scratch the body!

Carefully swipe the mediator around the perimeter, separating the screen from the frame. Be careful about the plume area of the display (top left) - it is easy to damage.

Step 4: Turn off the plumes

When the screen is separated, put it on a stand (for example, on the box from the phone).

1. Unscrew 4 T3 screws, fixing the metal plate over the plumes.
2. Carefully tweez the display and sensor plumes with tweezers.
3. Disconnect the battery plume (usually on the bottom right).

Now you can start replacing parts, for example, to remove the battery, you have to smear it with a plastic blade and pull it out, after peeling it off the body.

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Never use metal tools to separate the battery – this can break through the battery shell and cause fire!

Method 2: Quickly open the back cover (to access the back cover) SIM-tray)

If you need to get to SIM-If you're using a tray, antenna modules, or a rear camera, you can only remove the back cover without touching the screen, which is a less risky method, but you need to be careful.

Instructions:

1. Warm up the hair dryer around the perimeter (especially in the area of the camera).
2. Insert the plastic mediator into the gap between the lid and the frame (start with the lower right corner).
3. Carefully drive the mediator along the edge, separating the lid, which is held on the latches and glue.
4. When the lid moves, remove it completely. Be careful, it's got fingerprints on it. NFC-antennae!

To reassemble the phone, clean the glue residue from the frame and lid, apply a new double-sided tape (such as 3M 9448A) and press the lid, warming it up with a hair dryer for better fixation.

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If the NFC stopped working after assembly, check to see if the antenna plume has moved away from the motherboard, and often it's just not fully inserted into the connector.

Method 3: Disassembly without heating (risky method)

This method is only suitable in extreme cases when there is no hair dryer or time, the risk of damage to the screen or body is up to 70%, so use it only if other methods are not available.

What you need:

• Thin guitar string or fishing line (∅ 0.1-0.2 mm).
• Two plastic mediators.
• Scotch for string fixation.

Process:

Stretching the string between the screen and the frame, fixing its ends with tape on the back cover, carefully sawing the string along the edge, as if cutting glue. This method requires patience and accuracy — one wrong movement can scratch the display.

⚠️ Warning: A string can cut not only the glue, but also the plumes of the display if it penetrates too deeply!

Frequent Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling the Xiaomi Mi 9. Here are the most common problems and ways to prevent them:

If the phone does not turn on after disassembly, check:

• 🔌 Are all plumes connected (especially batteries and displays).
• 🔋 Does the battery swell (if so, replace it!).
• 📱 Is there any visible damage on the motherboard (blackened elements, traces of burns).

What to do after a successful disassembly?

Once you've achieved your goal (replace the battery, screen, or other component), you have to put the phone back together.

1. Clean contacts. Wipe the plumes and connectors with alcohol or a special contact fluid (for example, Contact Cleaner).
2. Apply new adhesive. Use 0.1-0.2 mm double-sided tape for the screen, B-7000 glue or its analogues for the battery.
3. Check before final assembly, plug the battery in and check if the phone is switching on, if the sensor and the cameras are working.
4. Sealing. After assembly, warm up the edges of the screen with a hair dryer (50-60°C) for better glue fixation.

If you have problems after assembly (such as NFC or vibrations not working), take the phone apart again and check:

• 📶 Connecting antenna plumes (they often fall out during assembly).
• 🔊 Contacts of speaker and microphone (can oxidize over time).
• 🔋 The density of the battery adhesive (if it hangs - fix it with tape).

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After you change the battery, be sure to calibrate it: completely discharge the phone, then charge it to 100% without interruption, which will extend the life of the new battery.

FAQ: Answers to Frequent Questions