Modern smartphones, including the popular Xiaomi Redmi Note 4, are designed with a monolithic design that often makes it difficult to access internal components without special equipment. The need to open the case can arise for various reasons: replacing a broken rear window, installing a new battery or cleaning the speakers from dust. Device owners often face the dilemma of carrying the gadget to a service center or trying to solve the problem themselves, saving money.
The dismantling process requires some training and understanding of the physical properties of the materials that make up the body. The back panel in this model is glued to the frame, rather than being held on latches, as in older versions of devices. This means that to successfully complete the operation, you will need not only accuracy, but also a specific set of tools, as well as heating the adhesive to a certain temperature.
In this article, we will discuss each step of the procedure in detail to minimize the risks of damage to fragile elements. It is important to understand that any interference with the design of the device can affect its tightness and warranty, so all actions are carried out at your own risk.
Tools and workplace preparation required
Before disassembling, you need to organize a comfortable and safe space, the work surface should be clean, flat and well-lit so that small screws and plumes are not lost and are clearly visible. It is recommended to use an antistatic mat or just a clean sheet of white paper, which will clearly see all the details.
You'll need a special toolkit to work with, which you can buy from electronics stores or order online, and the main tool is a thermophen or a regular hair dryer that can heat the edges of the body to 80-90 degrees Celsius, and without heating, the glue will not soften, and trying to separate the glass by force will lead to its destruction.
- 🔧 Suction cup for lifting glasses - necessary to create an initial gap between the lid and the frame.
- 🎴 Plastic blade (mediator) - for careful dissection of the adhesive layer without scratches.
- 🪛 Set of screwdrivers (cross Pentalobe and Phillips) - for twisting screws of fasteners.
- 🧴 Isopropyl alcohol or a special solvent of glue - facilitates the process of separation of glued parts.
⚠️ Warning: Never use metal tools (knives, needles) to cover the lid, as they can damage the battery or shorten the contacts on the board.
The process of heating and separation of the rear panel
The first and most important step is to warm up the perimeter of the back cover evenly. Turn the hair dryer on average power and direct the flow of hot air along all four sides of the housing, lingering at corners for about 15-20 seconds. The general heating procedure should take about 2-3 minutes to ensure that the glue inside reaches an elastic state.
Once the body is warm enough, place the suction cup at the bottom of the back, closer to the center, but not at the very edge. Pull the suction cup up, creating tension, and simultaneously inject a thin plastic card or spatula into the resulting microscopic slit. Movements should be sliding, parallel to the plane of the screen, so as not to damage the display matrix on the back side.
☑️ Preheating check
When the first edge is separated, don't rush to remove the lid completely. Swipe the plastic mediator around the perimeter of the device, carefully cutting the adhesive layer. Pay special attention to the area around the camera module and the fingerprint scanner, as there the adhesive can be applied more tightly. If you feel strong resistance, stop pulling and warm up the problem area with a hairdryer again.
What to do if the cover is broken when removed?
Dismantling internal components and access to the battery
After successfully removing the back cover, you will see the internal device of the smartphone. In Xiaomi Redmi Note 4, you immediately notice a large battery and a metal plate covering the bottom of the board and plumes. To continue access, you need to unscrew all the visible screws that fix this protective plate.
The fasteners can be of different lengths, so it's important to remember or fix each of them on the location diagram. Wrap a long screw into a hole for a short one can pierce the motherboard through, causing the device to fail permanently. Use a magnetic mat or a sheet of paper with signatures to sort the screws.
| Component | Type of screw | Number of | Location. |
|---|---|---|---|
| Lower fees | Little cross-sized | 2 pcs. | Near the charging socket |
| Protective bar. | Cross-middle | 10-12 pcs. | Downside perimeter |
| Battery anchorage | Spetsprop | 2 pcs. | Under a decorative sticker (rarely) |
| Dynamician | Little cross-sized | 2 pcs. | In the lower corner of the case |
By disabling the connector plumes (display, batteries, buttons), you can gain full access to the battery. In the Redmi Note 4, the battery is also planted on double-sided tape. To replace it, you will need to apply heating again and carefully undress the power supply with a plastic blade, trying not to deform it.
Nuances of work with a fingerprint scanner
One of the most delicate parts of the Redmi Note 4 disassembly is the fingerprint scanner module on the back, which is connected to the motherboard by a thin plume that passes through a special hole in the case, and if you unguardedly remove the cover, this plume is (very easy) to tear.
If you plan to simply clean the speaker or replace the battery, try not to disconnect the scanner unless absolutely necessary. However, if a rear window replacement is inevitable, you will have to carefully disconnect the scanner connector from the board.
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When assembling, make sure that the scanner plume is not clamped and laid with a sharp fold, otherwise the unlock function will stop working.
A common mistake is to lose a rubber sealing ring around the scanner lens. This small element ensures that the module fits tightly against the glass and protects against moisture and dust. Before installing a new cover, check for this ring and replace it with a new one if necessary.
Assembly of the device and restoration of leakage
The assembly process is reversed, but with the addition of new consumables. Old glue loses its adhesive properties after disassembly, so you can not rely on it. To reliably fix a new or old cover, you need to use a special adhesive sealant for electronics (for example, B-7000 or T-7000) or ready-made adhesive frames.
Apply a thin, uniform layer of glue around the perimeter of the frame of the body, avoiding the material from hitting the camera, sensors and speaker. Let the glue dry for 1-2 minutes to a sticky film state, then gently apply the back cover and press hard around the perimeter. For better grip, you can use stationery gums, stretching them across and along the body for 15-20 minutes.
⚠️ Warning: Excess glue protruding from the seams should be removed immediately until they are frozen using a dry wipe or cotton swab soaked in alcohol.
Once the lid is fixed, collect all the internal components, plug the plumes and check the touchscreen, speakers and microphone before the final screwing is done. Make sure that no screw is left out and all the plastic latches fall into place with a characteristic click.
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The quality of the assembly and the absence of backlashes after repair directly depend on the thorough cleaning of the old adhesive base before applying a new one.
Typical errors and precautions
The most common mistake of beginners is not enough heating of the case, which leads to cracks in the glass when trying to do it. Patience during the heating stage is the key to successful disassembly. Don't be afraid to warm the phone longer, modern lithium-polymer battery and electronics briefly withstand temperatures up to 90-100 degrees without damage.
Another common problem is the damage to the plumes when you mishandle the tool. Always visually monitor the position of the blade and do not enter it deeper than necessary to dissect the glue. If you feel that something is not going according to plan, it is better to stop, study the circuitry of the device again and continue with greater caution.
- ❌ Forgetting to turn off the battery before working with other plumes can lead to short circuit.
- ❌ Using superglue (cyanacrylate) instead of an elastic sealant will make the next repair impossible without breaking the body.
- ❌ Ignoring static electricity – work in antistatic gloves or touch a grounded metal object before work begins.
In conclusion, it is worth noting that the Xiaomi Redmi Note 4 self-disassembly is a great way to save money and gain valuable experience. However, if you are not confident in your abilities or are afraid of damaging the device, it is better to contact professional craftsmen with experience and warranty for the work performed.