Disassembly Xiaomi Redmi 4X: how to carefully remove the back cover without breakage

Removing the back cover of the Xiaomi Redmi 4X is a challenge that owners face when replacing a battery, repairing a camera or cleaning internal components. Despite its apparent simplicity, the procedure requires care: improper actions can damage latches, plumes or even a display module. In this article, we will discuss three officially approved methods of dismantling, detail the necessary tools and reveal the hidden feature of mounting the cover in the Redmi 4X, which even service centers do not mention.

The Redmi 4X (codenamed santoni) was released in 2017 and became one of Xiaomi’s most popular budget models due to its balanced performance and maintainability. However, its design has several pitfalls: for example, asymmetrical latches and a fragile plastic holder of antenna contacts. If you are planning a first-time dismantling, we recommend that you carefully study each stage, which will save you time and nerves.

Preparation for disassembly: tools and precautions

Before you start removing the lid, make sure you have everything you need, and not even one tool can turn a simple procedure into anguish.

• 🔧 Plastic mediator (or guitar mediator) – to disconnect latches without scratches.
• 🔥 Dryer or thermo-air station (up to 300 power)°C) - to soften the glue around the perimeter.
• 🧲 Magnetic screwdriver. T3 — for twisting screws (in Redmi) 4X cruciform screws are used).
• 📦 Suction cups (2 pcs) - will help to evenly pull the cover after heating.
• 🧴 Isopropyl alcohol (90%+) — glue-residue.

Important: Redmi 4X It does not have official certification for protection against dust and moisture (IP-No rating, but the manufacturer still uses a sealing adhesive around the perimeter of the lid, which means that you have to put in more effort on the first opening than you would on the second disassembly. If you plan to disassemble the device frequently (for example, to test modules), replace the adhesive with a 3M VHB — It retains elasticity and leaves no traces.

⚠️ Warning: Do not use metal blades or knives - they will damage the anode cover and can close contacts on the board. Even microscopic scratches on antenna tracks lead to signal degradation LTE and wifi.

Method 1: Classic Heated Dismantling (Recommended for Beginners)

This is a technique that's suitable for people who have never disassembled the Redmi 4X and are afraid of damaging the latches, and the idea is to heat the adhesive layer evenly, and then carefully separate the lid with suction cups and a mediator, and here's a step-by-step instruction:

1. Turn off your smartphone and remove the tray for SIM-Make sure the battery is at least 30% charged, which will eliminate the risk of sudden shutdowns when a possible circuit breaks.
2. Heat the hair dryer back cover around the perimeter for 2-3 minutes, keeping it at a distance of 5-7 cm The temperature should be 80-90 ° C (if the hair dryer does not have a thermal sensor, focus on the sensations - the cover should become warm, but not hot).
3. Place the suction cups on the top and bottom of the lid (near the camera and USB-C connector). Pull up carefully - if the lid does not lend itself, repeat heating for another 1-2 minutes.
4. Insert a plastic mediator into the gap, and slowly move it along the side faces, turning the locks off in turn, start at the upper right corner, where there are fewer antenna contacts.

Key point: in Redmi 4X, the left side of the lid is tightened because of the location of the antenna block. Don't put too much effort into reheating the problem area. If you hear a characteristic crunch, immediately stop dismantling, which means that one of the latches (usually next to the power button) has burst.

Method 2: Unheating (for power users)

If you don't have a hair dryer or you're afraid of overheating, you can do without heat treatment, but this method requires precise techniques and is only suitable for devices that have been disassembled before (the glue is less durable).

• 📱 Place the smartphone screen down on a soft surface (such as a microfiber wipe).
• 🔍 Insert a plastic blade into the gap between the lid and the case next to the 3.5 mm connector (this is the “weakest” place).
• 🔄 Carefully sway the mediator left-right, gradually deepening. Once you hear the first click, move 1-2 cm left and repeat the action.
• ⚠️ Do not try to separate the cover completely at once – this will lead to a break in the fingerprint scanner plume (it is located under the top of the cover).

The advantage of this method is that there is no risk of overheating components (for example, the NFC chip, which in the Redmi 4X is located next to the antenna unit). However, it takes 2-3 times longer and requires perfectly smooth movements. If the lid does not respond after 5-7 minutes of effort, you better go back to the method with heating.

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If the lid has started to move away, but it's stuck in the middle, don't pull it by force -- you probably forgot to snap the lock next to the speaker. Use the flashlight to light up the gap and find the problem spot.

Hidden latches and traps in the design of the Redmi 4X

Even experienced craftsmen sometimes face unexpected challenges when disassembling the Redmi 4X, and here are three critical nuances that are rarely mentioned in the instructions:

1. Additional lock under the camera: In addition to the main latches around the perimeter, the Redmi 4X has a small plastic “tongue” that holds the lid in the lens area. If it is not bent, the lid will “stick” when you try to remove.
2. Fingerprint scanner plume: it's glued to the lid with double-sided tape, and if you unscrupulously dismantle it, the plume can break away from the board, which will lead to loss of sensor functionality.
3. Antenna contacts: There are 4 spring contacts on the inside of the lid, which are responsible for communication, and they are easy to bend or tear off if you pull the lid at an angle.

To avoid problems, follow a simple rule: remove the lid strictly perpendicular to the body, without skewing. If you feel resistance, do not continue — go back to the heating of the problem area or check if all latches are snapped.

What to do after successfully removing the lid?

Once the lid is removed, you will have access to the internal components of the Redmi 4X. However, do not rush to start repairing immediately - follow a few mandatory steps:

1. 🧹 Clean the insides of the dust with a soft brush or a spray of compressed air. Pay special attention to the area around the speaker and connector. USB-C.
2. 🔋 Disconnect the battery by swiping a plastic blade around the black connector on the motherboard, which will prevent short circuits from further manipulation.
3. 📸 Take a picture of the plumes' location before they're turned off. 4X It is easy to confuse the camera connectors and the fingerprint scanner - they are visually similar.
4. 🔧 Check the integrity of the antenna contacts. If they're bent, straighten them gently with tweezers.

If you're looking to replace your battery, consider that the Redmi 4X has it glued to the body with double-sided tape, and to remove it, put it in a plastic blade on the lower left corner (there are fewer components on the board). Don't use metal tools, because the risk of battery puncture is extremely high!

⚠️ Warning: After the battery is turned off, the smartphone can turn on itself when connecting the charger - this is normal for Redmi 4X. However, if artifacts appear on the screen (strips, flickering), this is a signal of damage to the display plume during disassembly.

Building a device: how to avoid errors

Putting the lid back in place is as important as removing it, and here's a step-by-step algorithm that will help you avoid the typical mistakes.

• 🔄 Check all connectors: Before assembly, make sure that the fingerprint scanner plume and the camera are tightly connected (a click should be heard).
• 🧴 Clean the body perimeter with isopropyl alcohol, and the glue residues can prevent the lid from fitting tightly.
• 🔥 Apply a new glue: Use B-7000 or 3M VHB, Avoid the area around the speaker and microphone.
• 📱 Set the lid starting at the top edge (near the camera) and press it carefully around the perimeter, avoiding skewing.
• 🔧 Twirl the screws in the following order: first the top (near the camera), then the bottom (near the camera). USB-C), and then later on.

After assembly, turn on the smartphone and check:

• 📶 The operation of antennas (network signal, Wi-Fi, Bluetooth).
• 🔊 Sound from speaker and microphone.
• 📷 Functionality of the camera and fingerprint scanner.

If something doesn't work, re-assemble the device and check the integrity of the plumes and contacts, and in 90% of cases, the problem is a loosely connected connector.

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Never turn on a smartphone with an incompletely assembled cover – this can lead to the closure of antenna contacts and failure of the communication module.

Frequent mistakes and how to fix them

Even with careful disassembly, you can make mistakes that lead to malfunctions, and let's look at the most common problems and how to fix them:

If after assembly you notice that the body warms more than usual, this may indicate:

• 🔋 Poor battery contact (check the connector).
• 📡 Closed antenna contacts (disassemble and inspect the cover).
• ⚡ Damage to the motherboard (diagnosis is required at the service center).

In most cases, the problems are solved by re-disassembling and thoroughly checking all connections, but if you damage the board or plumes, professional repair may be necessary.

FAQ: Answers to popular questions