Xiaomi Redmi 4 Note, also known as Redmi Note 3 Pro in some regions, remains a popular device due to its reliability and performance. However, time is inexorable: even the best quality lithium polymer battery loses capacity over time, stops holding charge and can suddenly turn off when you load. If your phone runs out in a couple of hours or shows surges in percentages of charge, it’s time to think about replacing the power source.
The process of self-replacement requires precision, basic tools, and an understanding of device design. Unlike many modern monolithic smartphones, the Redmi 4 Note design allows you to reach the battery relatively safely if you follow a certain sequence of steps. In this article, we will discuss in detail all the steps from preparing the workplace to the final calibration of the new battery so that you can return your gadget to a second life.
It is important to understand that opening the case can lead to a loss of warranty if it is still relevant, and also requires caution when working with adhesive joints. Wrong actions can damage the plumes or the screen itself. However, with proper preparation and the presence of a quality original battery or its proven counterpart, the procedure takes no more than 40-50 minutes even for a beginner.
Diagnostics and selection of a new battery
Before starting to disassemble, you need to make sure that the problem lies in the physical wear of the chemical element, and not in the software failure or malfunction of the power controller on the motherboard. Often users confuse battery wear with the “glitch” of the MIUI operating system. For accurate diagnosis, you can use special applications or built-in codes of the engineering menu.
Enter the code ##6485## in the application "Phone" and pay attention to the parameters MB_06 (the state of battery health; and MF_05 (Number of charging cycles: If the condition is assessed as “Bad” or the number of cycles exceeds 500, The replacement is inevitable, and the battery is also a sign of malfunction, as you can see from the back cover that has moved away or the touchscreen bulging.
When choosing a new battery, it is critical to pay attention to the marking and capacity. The Redmi 4 Note is standard with a capacity of 4100 mAh. There are many overrated fakes on the market that do not last long. Look for models labeled BM46 or BN46 (depending on the specific revision of the board), checking the presence of holograms and the quality of printing the Xiaomi logo.
⚠️ Warning: Never reuse a bloated battery and do not attempt to prick it with a needle to "extinguish gases" This can lead to instant lithium ignition and chemical burns.
The quality of the placement component directly affects the stability of the Snapdragon processor. Cheap counterparts often cannot deliver the necessary current at peak load moments, which leads to unexpected reboots of the device under load, so the savings on the battery in this case are false savings.
Tools and workplace preparation required
The success of the operation depends on 80 percent proper preparation. You don't need complex industrial equipment, but a suite of specialized tools is a must, and using inappropriate items like knives or pins greatly increases the risk of damage to internal components or injury.
Organize a workspace in good lighting. The table surface should be clean, flat and preferably covered with soft material so as not to scratch the smartphone body and lose small screws. It is also recommended to use an antistatic mat or simply work without synthetic clothing to prevent damage to electronics by static electricity.
To work, you will need the following set of tools:
- 🔧 Torx screwdriver set T5 cross-block (PH000) hull-screw.
- 🎴 Plastic mediators or old plastic cards to peel off the lid.
- 🌡️ Hair dryer or heating pad for softening glue (temperature not higher) 80-90°C).
- 🧲 Magnetic mat or a tank for sorting screws of different sizes.
- 🧤 Tweezers with dielectric sponges for working with plumes.
Pay special attention to the heating tool. Household hair dryer may not give enough temperature, so it is better to use a building hair dryer with the ability to adjust the temperature or a special heating pad for smartphones. Overheating the screen above 100 ° C can damage the polarization film or peel the touchscreen.
☑️ Checking readiness for repair
The process of disassembling the body Xiaomi Redmi 4 Note
Disassembly of the Redmi 4 Note begins with the removal of the SIM card and the microSD tray. After that, you need to unscrew the two screws located at the bottom of the device near the charging connector, which are hidden by decorative plugs or are visible immediately, depending on the color of the case.
The next step is to heat the perimeter of the back cover. Warm up the ends of the smartphone evenly for 2-3 minutes. Don't hold the hair dryer at one point so as not to overheat the display matrix on the back side. After warming up, insert the plastic mediator into the junction between the frame and the cover and carefully guide along the perimeter, cutting the adhesive layer.
When the lid is unstuck, don't pull it sharply. Inside, on the right side (when viewed from the back), there's a wide plume of the fingerprint scanner that connects the lid to the motherboard. Careless movement can break off this thin conductor, after which the scanner will stop working forever.
| Element | Type of attachment | Tool. | Risks. |
|---|---|---|---|
| Back cover. | Glue + screws from the bottom | Fen, mediator | Scanner plume breaks |
| Plastic protection | Torx T5 screws | Screwdriver T5 | Breaking of thread under heavy pressure |
| ACB | Adhesive tape + connector | Plastic spatula | Puncture of the battery body |
| plumes | Locker latches | Tweezers, nails. | Connector latch failure |
Once you remove the lid, you'll see a plastic pad covering the bulk of the components, and it's fixed by a lot of screws around the perimeter and in the center, and you'll have to twist them all out in order, because the screws can be of different lengths, and a short screw screw screw screwed into a long hole can break through the board.
Removing the old battery and installing a new one
Once you remove the plastic, you'll have access to the motherboard and the battery, and the first thing you need to do is to disconnect the battery plume from the circuit board connector, and you need to do this carefully, by putting a plastic blade or nail on the connector, but by no means with metal tweezers, so you don't close the contacts.