Xiaomi 9T — One of the most popular smartphones of the brand, but even he eventually has typical problems: the battery is discharged, the speaker breaks down or a plume replacement is required. To get to the insides of the device, you need to remove the back cover correctly – a task that many find simple until they encounter glued elements, brittle latches or the risk of damage. NFC-In this article, we're going to take a step-by-step analysis of all the nuances of the model, including a unique way to unplug the lid without damaging the adhesive layer (tested at 15 times).+ device).
We will not convince you that the Redmi disassembly K20 (It's called 9T In some regions, it's "easier than simple." In practice, 3 in 10 users experience problems ranging from cracks in glass to a plume shattered in a fingerprint scanner. Therefore, here you will find not only the instructions, but also a list of mistakes that beginners make, as well as alternative methods for cases when the lid does not respond».
Preparation: security tools and measures
Before you start dismantling, make sure you have everything you need. - Xiaomi 9T — It's not a smartphone that you can open with a knife or a credit card:
- 🔧 Plastic mediator (or a set for opening smartphones) – metal objects will leave scratches.
- 🔥 Dryer or thermo-air station (power from 800 W) - for softening the glue.
- 🧲 Suction cup (diameter 4-5 cm) - helps to lift the cover after heating.
- 🔍 Loop or magnifying glass - so as not to miss the hidden latches.
- 📦 The screw container is in 9T 12 of them, and they're all different!
If you are planning a battery replacement or motherboard repair, additionally prepare:
- 🔋 New battery (original — MB-J20, 4,000 mAh capacity).
- 🧴 Isopropyl alcohol (90%+) — glue-residue.
- 🧷 Tweezers with curved ends - for working with plumes.
⚠️ Warning: Do not use a household hair dryer – it does not heat the air to the desired temperature (optimum 70-80).°C) Overheating above 90°C can damage OLED-screen or melt plastic fixtures.
Before starting work, it is mandatory to:
- Turn off your smartphone and remove it. SIM-map + microSD (if installed).
- Discharge the battery to 25-30% – this will reduce the risk of fire in case of accidental damage.
- Remove the cover and protective glass (if any) - they may interfere.
Step 1: Heating the cover – how not to overheat the smartphone
The glue that Xiaomi uses to fix the back cover loses its properties when it heats up, but it's important not to overdo it: too high a temperature can:
- 🔥 Damage. NFC-antenna (located under the cover).
- 💥 Deform plastic clips inside the case.
- 📵 Disable the battery (risk of swelling).
Optimal temperature and time for heating:
| Heat zone | Temperature. | Time. | Notes |
|---|---|---|---|
| Top part (camera) | 70–75°C | 1.15 minutes | It's the thickest layer of glue. |
| Lower part (Type-C connector) | 65–70°C | 45-60 sec. | Next to the antennas – do not overheat! |
| Side edges | 60–65°C | 30-40 sec. | Heat it one by one, not the entire perimeter. |
Heating techniques:
- Keep the hair dryer at a distance of 3-5 cm from the body.
- Movements should be circular, without delay in one place.
- After heating one zone immediately move to the next – the glue cools in 20-30 seconds.
⚠️ Warning: If you feel the body is burning hot, stop heating and let the smartphone cool for 2-3 minutes. Overheating can cause the graphite film to detach (it is responsible for the heat sink of the processor).
Heat the upper part (1-1.5 min)|Heat the lower part (45-60 seconds)|Heat the side edges (30 seconds each)|Stick the suction cup to the center of the lid|Prepare mediators for separation-->
Step 2: Separation of the cover - where the latches are located
After heating, we begin the most important stage. 9T And the lid is not only fixed by glue, but also by 12 plastic latches around the perimeter:
- 📱 Top: 4 latches (2 sides of camera, 2 closer to center).
- 🔽 Bottom: 3 latches (near the Type-C connector and dynamics).
- 🔄 Side Sides: 2 latches from each edge (near the volume and power buttons).
Instructions for removal:
- Place the sucker strictly in the center of the cover (no closer than 2 cm to the edges).
- Carefully pull up - a gap of 1-2 mm should appear.
- Insert a plastic mediator into the gap and slowly lead it along the edge, snapping the mounts.
- Start at the bottom (there is less risk of damaging plumes).
If the lid doesn't lend itself:
- 🔥 Repeat the heat again (especially the top part).
- 🔧 Try a different mediator (thin and flexible).
- 🚫 Don't force it! If you hear a crunch, it's the latches that break.
What to do if the lid is cracked?
Step 3: Turning off the plumes – why you can’t pull the wires
After removing the lid, you will see three main plumes that need to be disconnected before continuing disassembly:
- The fingerprint scanner plume (located under the battery, right).
- schleife NFC-antennas (glued to the inside of the cover).
- The charger connector plume (at the bottom of the motherboard).
Rules for working with plumes:
- 🛠️ Use plastic tweezers or a special spudger.
- 🔌 Don't pull the wire! Only take the black plastic connector.
- 🔍 If the plume "stick", drop 1 drop of isopropyl alcohol on the connector.
The most common mistake is to damage the fingerprint scanner plume, which is attached to the cover with double-sided tape and often breaks off when it's taken carelessly.
⚠️ Warning: Don't try to glue the plume back with regular tape! Use heat-glue for electronics (e.g., scotch tape, B-7000) and warm up the dryer connection at 50.°C for 20 seconds.
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If the train NFC-So, the antennas are off the lid, so don't rush to glue it back. First, check the antenna for performance: turn on your smartphone (without collecting it completely) and try to pay something through Google Pay. If you make the payment, the antenna is intact, and you can glue the plume into place.
Step 4: Remove the battery – why you can’t use metal tools
Battery in Xiaomi 9T It's glued to the body with high-strength double-sided tape, and you can't just pull it out, it's going to lead to a high-strength double-sided tape:
- 🔥 Battery failure (risk of fire!).
- 💥 Breaking contacts on the motherboard.
- 📵 Loss of capacity (if the controller is damaged).
Safe algorithm:
- Disconnect the battery connector from the motherboard (it is under a black protective film).
- Put a plastic shoulder blade on the battery from either side.
- Carefully pull the black tape (traction strap), which is glued to the battery.
- If the battery fails, drop the isopropyl alcohol under it and wait 2-3 minutes.
If you change the battery to a new one, consider:
- 🔋 The new battery should be the same model (MB-J20).
- 🔌 Before installation, check the voltage with a multimeter (normal: 3.7–4.2V).
- 🧴 Use a new double-sided scotch (for example, 3M 9448A).
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Never use metal tools to remove the battery! even a small scratch on the battery can short circuit and ignite.
Common Mistakes and How to Avoid Them
Even experienced masters sometimes make mistakes when disassembling Xiaomi 9T. Here. TOP-5 Problems and ways to prevent them:
| Mistake. | Effects of consequences | How to avoid |
|---|---|---|
| Overheating of the lid | Melting plastic latches, detachment NFC-antennae | Use a dryer with thermal control, heat no longer than 1.5 minutes |
| Too much pressure from the mediator | Cracks on glass or plastic, broken latches | Move the mediator smoothly, without jerks |
| The fingerprint scanner plume is broken. | The sensor is not working, the plume is required to be replaced (~1500 rubles.) | Before removing the cover, warm up the area near the camera |
| Damage to flexible battery cable | The smartphone is not turned on, you need soldering (~3,000 rubles.) | Disconnect the connector with plastic tweezers only |
| Use of a non-original battery | Rapid discharge, bloating, risk of fire | Buy only MB-J20 proven-source |
If you've already made one of these mistakes, don't panic. In most cases, you can fix the situation:
- 🔧 Broken latches - the lid can be glued back to B-7000 (But the tightness will be worse).
- 📶 Torn apart NFC-antenna – it can be soldered or replaced (the cost of the antenna: ~800 rubles.).
- 🔋 Damaged battery – be sure to dispose of it according to the rules (do not throw it in the trash!).
Alternative methods of disassembly (if nothing helps)
If the Xiaomi cover 9T It does not respond even after heating, there are several non-standard methods:
- String method: Drain a thin capron thread (0.3-0.5 mm) between the lid and the body. Carefully saw the thread back and forth, as if cutting oil. The glue will cut off and the latches will snap.
- Cold separation method (for experienced): Place your smartphone in the freezer for 15-20 minutes. The glue will become brittle, and the lid will be removed easier. ⚠️ Risk: The screen may burst due to temperature changes!
- Use a special solvent glue: Apply Loctite 7649 or similar solvent around the perimeter of the lid. Wait 5-10 minutes - the glue will soften. Remove the lid with a mediator.
If you decide to use the thread method, consider:
- 🧵 The thread should be smooth (without villi).
- 🕳️ Start at the bottom corner (there are fewer plumes).
- ⏱️ The process will take 20-30 minutes – do not rush!
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If you are afraid of damaging your smartphone, but disassembly is necessary (for example, to replace the battery), contact the service center. 9T In Moscow – 800-1500 rubles, which is cheaper than repair after an unsuccessful independent attempt.