Xiaomi Mi 4X (also known as Mi 4c in some regions) is a popular 2015 model that is still used by many users, and may need to be disassembled over time to replace the battery, clean the dust, repair connectors, or even upgrade the memory. But how do you do it correctly without damaging fragile components?
In this article, you will find a step-by-step photo guide, a list of tools you need, and key warnings to help avoid typical mistakes. We will also discuss when to disassemble the best for professionals, and when to do it yourself. If you have never disassembled a smartphone, don’t worry: the Mi 4X is one of the models with medium complexity of disassembly, and even a beginner can cope with the task with accuracy.
⚠️ Important: Disassembling your smartphone will void the warranty (if it's still valid), and inside the device are a lithium battery and chips that, if handled carelessly, can fail or even ignite. If you're not sure about your abilities, contact the service center.
1.Preparation: tools and conditions
Before you start disassembling, make sure you have everything you need. Xiaomi Mi 4X has adhesive back mount and brittle plumes, so a regular screwdriver will not be enough. Here is the full list of tools:
- 🔧 Plastic mediators (2-3 (S) for a careful sleeve of the lid.
- 🔨 The screwdriver. PH00 — screw-hole.
- 🧲 Suction - will help remove the back panel without scratches.
- 🔥 Hair dryer or thermoair station - for softening the glue (optional, but recommended).
- 📦 Container for screws - so as not to lose small details.
- 🧴 Isopropyl alcohol (90%+) — Cleaning contacts and removing glue residues.
Also, prepare the workplace: it should be well lit, draft-free (dust can get inside the smartphone) and with a soft substrate (for example, a silicone mat) so as not to scratch the case. If you use a hair dryer, do not direct hot air to the screen or battery for more than 10 seconds in a row!
Step 1: Turn off and remove the back cover
The first stage is the most important. The Mi 4X has an aluminium body with adhesive attachment, so you need to remove the lid carefully so you don't bend.
- Turn off your smartphone and remove it. SIM-card and memory card (if installed).
- Heat the back panel with a hair dryer (~60°C) around the perimeter for 1-2 minutes. This will soften the glue.
- Suction the top of the lid (near the camera) and pull up.
- Insert a plastic mediator into the resulting gap and carefully lead it along the body, separating the lid.
Don't use too much force! If the lid doesn't respond, warm up the problem area again. On the Mi 4X, the corners around the antenna lines (upper and lower) often stick. Be especially careful with the fingerprint scanner plume, which attaches to the lid and can come off.
What to do if the lid is not removed?
Step 2: Turn off the battery and plumes
When you take the lid off, you'll see the battery, the motherboard and a few plumes. First rule: always turn off the battery before you do anything! On the Mi 4X, it's like this:
- 🔋 Find the battery connector (usually located at the bottom of the board, marked in red or orange).
- 🛠️ Carefully tuck the connector into a plastic pickup or tweezers. Don't use metal tools!
- ⚡ Plus, if the battery is swelling, don't try to remove it yourself. It's dangerous.
Next, disconnect all the plumes that are attached to the motherboard:
- Display plume (top of board).
- Camera plume (usually on the right).
The home button plume (if physical).
- The fingerprint scanner plume (if it is separate).
Is the battery off?|All plumes are disconnected?|Motherboard screws twisted?|Photo of the insides taken (for reverse assembly)?-->
⚠️ Attention: On Mi 4X The plume is extremely fragile. If you damage it, it'll cost you to replace it. 30-50% When you disconnect, pull the plastic connector, not the wires!
Step 3: Removing the motherboard
The Mi 4X motherboard is mounted on 8-10 screws (depending on the modification), all of which are of different lengths, so remember or photograph which screw is twisted from where.
| Vint | Size | Location | Note |
|---|---|---|---|
| 1 | 1.5 mm | Upper left corner | Shortest one. |
| 2-3 | 2.0 mm | On the sides of the battery | Average length |
| 4-5 | 2.5 mm | The bottom of the fee | The longest. |
| 6 | 1.8 mm | Under the camera plume | They often forget to twist! |
After you unscrew the screws, you can gently raise the board with a plastic mediator, and it can stick to the heat conductive paste on the processor -- don't pull it out. If the board doesn't work, check:
- Are all screws twisted?
Have you forgotten to disconnect the plume of the vibrating motor (it is attached to the bottom of the board)?
💡
If you're disassembling the Mi 4X to replace the battery, you can stop at this point. The battery is attached to double-sided tape -- tuck it in with a plastic card and carefully remove it. The new battery is glued to fresh tape (e.g., 3M 9448A).
Step 4: Disassemble the display and buttons
If you need to replace a screen, a digitizer, or a button, you have to go further. The Mi 4X display is glued around the perimeter, and it takes patience to remove it. Here's how to do it:
- Heat the screen with a hair dryer (temperature ~50°C) at the edges.
- Insert a plastic mediator into the gap between the screen and the frame (start at the bottom edge).
- Carefully drive the mediator along the display, separating the glue. Don't press too hard - the glass may crack!
- After the adhesive is separated, raise the screen and disconnect the digitizer plume.
The Volume and Power buttons on the Mi 4X often stick or stop working to extract them:
1. Remove the metal latches that hold the buttons (they are attached to small screws).
2. Carefully pluck the buttons on the back of the case.
3. Clean the contacts with isopropyl alcohol if they have oxidized.
⚠️ Note: On some versions of the Mi 4X The Power button is connected to the plume that goes to the motherboard, and if you damage it, the button will stop working and the repair will cost you nothing. 1500-2000 ruble.
6.Typical problems and how to avoid them
Even with a careful disassembly, you can run into trouble, and here are the most common mistakes and ways to prevent them:
- 🔋 Bloated battery: if the body Mi 4X You're going to start to "bubble up" and don't try to disassemble it.
- 📱 Cracked screen: if the display is already broken, paste it with tape before disassembling so that the fragments do not crumble.
- 🔌 Teared plumes: always pull the connector, not the wires. If the plume does come off, it can be soldered, but it requires experience.
- 🔧 Lost screws: use a magnetic mat or container with cells. 4X They are easily lost due to their small size.
Another common problem is that the fingerprint scanner is broken after assembly, and this happens if:
- The scanner's plume is not connected correctly.
- The contact area on the board is damaged.
Forgot to install a metal gasket under the scanner (it is needed for grounding).
1. Is the battery connected?
2. Is the motherboard correctly installed (are there no clamped contacts)?
3. Have you forgotten to plug in the power plug of the Power button?-->
7.When to disassemble is better to trust the professionals
Although the Xiaomi Mi 4X can be disassembled on your own, in some cases it is better to contact the service center:
- 💥 The battery is swelling or deformed.
- 📲 Requires replacement of chips (for example, a power controller or flash memory).
- 🔍 You need to re-sweat the charging connector or headphones (a soldering station and experience are required).
- 🌡️ Smartphone overheats or shuts down for no reason (possible processor problems).
The average cost of disassembling the Mi 4X in the service is from 800 to 1500 rubles (excluding spare parts).If you are not sure about your skills, it is better to pay for professional assistance than risk the device's performance.
⚠️ Note: If you are disassembling a smartphone for sale “on parts”, please note that some components (such as the motherboard or camera) can be tied to the serial number of the device.