Replacing the battery, repairing the broken rear window, or cleaning the internal components from dust all require access to the insides of the smartphone. Xiaomi Redmi 7 (codenamed onc) has a plastic back panel, which theoretically simplifies the dismantling process compared to glass counterparts. However, the design of the device involves the use of glue to seal the case, which requires accuracy and specific tools.
Owners often face difficulties in the initial opening, fearing damage to the plumes or scratch the body. Incorrect actions can lead to the fact that the lid will hang or cease to protect against moisture and dust. Before starting any manipulations, you need to clearly understand the sequence of actions and have the necessary set of tools for careful disassembly at hand.
In this guide, we will take a detailed look at the process of dismantling the back panel, paying special attention to the nuances of working with adhesives and brittle plumes. Compliance with the technology will allow you to perform the replacement of components without risk to the main device.
Tools and workplace preparation required
Good disassembly begins long before you pick up the first tool, you need to prepare a good lighting workplace to see the small screws and suction cup entry points, and the absence of dust and foreign objects minimizes the risk of losing small parts during the work.
The basic toolkit includes a suction cup, a mediator (plastic blade) and a set of screwdrivers. For the Redmi 7, it is critical to use plastic tools to tamper with the body, as metal can easily damage plastic latches or scratch the frame.
- 🔧 Plastic blade (mediator) for opening the body without damage.
- 🌀 Suction cup for careful pulling of the back cover from the frame.
- 🌡️ Hair dryer or heat pad to soften glue around the perimeter.
- 🪛 Phillips screwdriver (cross) for twisting screws under plugs.
The heat treatment is particularly important, because the glue used by the manufacturer holds the lid very tight at room temperature, and when you try to open a cold phone, it often ends up cracking the plastic in the back.
⚠️ Warning: Do not use open fires (lighters) to heat. Redmi 7 back cover plastic can warp or change color when locally overheated.
Technology of safe heating of the body
The softening process is the most critical part of the preparation. You need to warm up the perimeter of the device evenly. The optimal heating temperature is about 80-90 degrees Celsius, but without the thermometer, it is better to focus on the tactile sensation: the body should become hot, but not burning.
Use a dryer, holding it 3-5 cm from the surface. Move the airflow around the perimeter of the back cover, lingering at the corners and edges where the glue is usually the most. The heating process takes 2 to 4 minutes depending on the power of your tool.
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Check the temperature with your finger: if you can hold your finger on the heated area for 2-3 seconds, then the glue has softened sufficiently.
Take your time and try to lid immediately after the dryer is turned on. Insufficient heating will cause the plastic to crack under the pressure of the shoulder blade, and the adhesive layer will break unevenly.
Alternative heating methods
Step-by-step process of opening the back panel
Once the case is warmed, place the suction cup at the bottom of the back cover, closer to the center, but not on the logo. Press a little to ensure a tight fit, and pull up, creating a small gap between the frame and the plastic.
Insert a plastic blade into the gap, do not go too deep into the tool so as not to damage the internal plumes, move the blade along the perimeter, gradually cutting the adhesive layer, exercise special care in the lower part, where antenna terminals can pass.
☑️ Autopsy phases
When all sides are passed, the lid should be easily separated. If you feel resistance, don't pull force, go back to the problem area and repeat the heating and cutting of the glue.
| Risk zone | What's under the lid? | Precautions |
|---|---|---|
| The bottom part | Charging port plume, antenna | Do not enter the shoulder blade deeper than 3-4 mm |
| Upper part | Main board, display plume | Move slowly, without jerking |
| Central part | Battery, vibrator motor | Avoid battery punctures with a point |
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The first mistake of beginners is to try to tear the lid off immediately after the first gap is created, and the glue needs to be cut off around the perimeter.
Dismantling screws and disconnecting plumes
When you remove the back cover, you can see the interior of the smartphone, but you can't immediately remove the battery or other components. Most of the internal modules in the Xiaomi Redmi 7 are covered with plastic protective pads that are fixed by screws.
First of all, you need to unscrew the screws that hold the main board and the charging module, which are usually hidden under small rubber plugs or located around the perimeter of plastic screens, and use a magnetic screwdriver to avoid dropping the screws inside the case.
- 🔋 Turn off the battery plume first - this will power out the device.
- 📱 Carefully disconnect the plumes of the display and touch screen.
- 🔌 Remove the connectors of the main and front cameras.
- 📡 Disable antenna cables if they interfere with access.
When working with connectors, use a plastic shoulder blade or nail. Metal tools can damage the contacts on the board, which will cause the corresponding module to fail. Movements should be directed upwards, not to the side.
⚠️ Attention: The plumes in Redmi 7 are quite thin. When you turn them off, hold the board with your finger so that you don't tear the connector off with the plume.
Once all communications are shut down, you can start removing the battery or other replacement cells, and if your goal was just to replace the battery, then the main difficulties are already behind you.
Nuances of work with adhesive base and assembly
The assembly of the device requires as much attention as disassembly, the old adhesive layer must be completely removed from the frame and the lid itself, and it is convenient to use alcohol or a special solvent, as well as a plastic card to scrape the residues.
To seal the case at home, it is best to use a special glue B-7000 or T-7000. It has sufficient elasticity after drying, which allows you to remove the lid again in the future without undue effort. Apply a thin strip of glue around the perimeter of the frame, avoiding hitting the camera and speaker.
After applying the glue, combine the lid with the frame and press tightly around the perimeter. For better fixation, you can wrap the phone with rubber bands or put it under the press (for example, under a stack of books) for 1-2 hours until completely dry.
It's important not to overdo it with the amount of glue. The excess that has come out can be carefully removed with a cotton swab dipped in alcohol until the glue is frozen. The frozen glue will be much more difficult to remove.
Possible problems and solutions
Unforeseen situations may occur during disassembly, such as the lid may crack in the corner if it is not opened properly, and it is recommended to replace the back panel with a new one, as the cracked plastic will continue to break down during further use.
Another common problem is a severed plume, where if the connector is left on the plume and the board is bare, contact can only be restored at the service center with a microscope and soldering, and self-attempts to glue the plume with tape rarely yield long-term results.
- 🛑 The cover is not removed: Reheat the hair dryer during 1-2 minute.
- 🛑 The screw does not twist: Check if the thread or screw cap is ripped off.
- 🛑 Phone not turned on: Check the connection of the battery plume and display.
⚠️ Warning: If the phone has stopped responding to charging after assembly, check the charging port connector.
It’s also worth remembering that self-disassembly deprives the device of warranty if it was still in operation, but for the Redmi 7, released a few years ago, this factor usually no longer plays a role.