Xiaomi Redmi 7A is one of the brand’s most popular budget smartphones, but repairing or replacing the battery often requires removing the back cover. This procedure seems simple only at first glance: improper actions can lead to cracks in the plastic, damage to the fingerprint scanner plume or even failure of the motherboard. In this article, we will analyze the step-by-step dismantling algorithm, suitable tools and critical nuances that even experienced craftsmen ignore.
The design of the Redmi 7A is different from Xiaomi’s flagship models: there is no glass back, but the plastic latches are brittle, and the adhesive tape under the lid can complicate the process. If you plan to replace the battery, speaker or microphone, this instruction will help avoid typical errors. For visual support, we recommend watching the video disassembly (links at the end of the article), but first – theory and preparation.
Preparation: security tools and measures
Before you start disassembling, make sure you have everything you need, and if you don't have at least one tool, you can damage the body or the internal components, and here's the minimum set:
- 🔧 Plastic blade (or mediator) to separate the latches. Metal tools scratch the plastic!
- 🔥 Hair dryer or thermo-air station - for softening the glue (temperature not higher than 70)°C).
- 🧲 Suction cup - helps to lift the cover after heating (diameter 3-5 cm).
- ⚡ Antistatic bracelet – protects the motherboard from static electricity.
- 📦 The screw container - at Redmi 7A They are few, but losing even one will make it harder to assemble.
Important: Redmi 7A It does not have an official degree of protection from moisture (IP-So disassembly in high humidity (e.g., in the bathroom) can lead to corrosion of contacts. Work on a dry, flat surface with good lighting. If you've never disassembled a smartphone, practice on a non-functioning device or watch the video manual until the end.
⚠️ Warning: Do not use a knife or screwdriver to lash the lid - this is guaranteed to damage the latches.Redmi Plastic 7A It is thinner than the Redmi Note series and cracks even at low pressure.
Step 1: Turn off and discharging static electricity
Before disassembling, be sure to turn off the smartphone and remove SIM-Even when it's off, there may be a residual charge on the board that will damage the components when you touch it:
- Press and hold the power button for 10-15 seconds to make sure you are completely off.
- Touch the metal body of the PC system unit or heating battery – this will remove static electricity from your hands.
- Wear an antistatic bracelet (if any) and ground it on a metal surface.
In the Redmi 7A, the battery plume does not automatically turn off when the lid is removed - this is a key difference from models with a removable battery (for example, the Redmi 4A).
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If you don't have an antistatic bracelet, wrap your fingers in foil and ground it on the battery. This is a temporary but working alternative.
Step 2: Heating the cover to soften the glue
The back cover of the Redmi 7A is attached to perimeter duct tape and plastic latches, and to separate it without damage, the glue must be softened.
- Set the dryer to a minimum power and temperature of 60–70°C (higher values deform plastic).
- Heat the lid around, paying special attention to the corners, which is where the glue is greatest. Heat time: 2-3 minutes.
- Check the temperature with your hand (carefully!): the lid should be warm, but not hot.
Alternatively, use a thermoplatform (if available), in which case 1-2 minutes at 50°C. Do not overheat the device: if the plastic begins to smell, stop heating immediately!
| Method of heating | Temperature. | Time. | Risks. |
|---|---|---|---|
| Fen | 60–70°C | 2-3 minutes | Local overheating |
| Thermoplatform | 50°C | 1-2 minutes | No (uniform heating) |
| Hot water (not recommended!) | ~40°C | 5-10 seconds | Short circuit, corrosion |
⚠️ Warning: If you use a hair dryer, keep it 10 to 15 cm away from the body. Direct hot air flow can melt plastic latches near the camera.
Step 3: Separating the cover with a suction cup and a shoulder blade
After heating, start removing the lid.
- Apply the suction cup to the bottom of the lid (near the USB-C connector).
- Carefully pull up - a small gap (1-2 mm) should appear.
- Insert a plastic blade into the gap and slowly lead it along the edge, snapping the mounts.
- Pay special attention to the area near the volume and power buttons - there the latches are the most fragile.
If the lid doesn't lend itself, don't apply force. Go back to heating for another 1-2 minutes. In the Redmi 7A, there's a common problem: the glue near the fingerprint scanner is stronger than in other areas.
- 🔹 Heat the scanner area separately.
- 🔹 Use the second shoulder blade to evenly distribute the pressure.
- 🔹 Don’t try to tear the lid off with a jerk – it will tear the scanner plume!
Heat the entire perimeter of the lid.|Suction cup fits tightly|The blade is inserted into the gap at an angle of 15-20°|No sudden movements.-->
Step 4: Disconnect the plumes and battery
When you take the lid off, you'll see the insides of the smartphone. First rule: don't touch the motherboard with your bare hands! Static electricity can damage the chips.
- Check the plumes: 📱 Battery plume (black, with red marker). 👆 Fingerprint scanner plume (thin, white). 🔊 Dynamic plume (if it is in your modification).
battery-line
Then disconnect the fingerprint scanner plume - it is attached with a latch, which must be carefully lifted.
In the Redmi 7A, the battery plume is inconveniently located: it is partially covered with a metal screen. If the blade does not pass, use tweezers with insulated ends.
What happens if you don't turn off the battery?
After the plumes are turned off, you can proceed to further disassembly (battery replacement, speaker, etc.).If your goal is only to remove the lid (for example, to clean the dust), do not touch other components unnecessarily.
Common Mistakes and How to Avoid Them
Even experienced users make mistakes when disassembling the Redmi 7A. Here are the most common of them and ways to prevent:
| Mistake. | Effects of consequences | How to avoid |
|---|---|---|
| Use of metal tools | Scratches on plastic, circuits on board | Use only plastic blades |
| Overheating of the cover (>80°C) | Deformation of plastic, detachment of paint | Control the temperature with a thermometer |
| Sharp compartment of the lid | Fracture of the fingerprint scanner plume | Slowly drive the shoulder blade around the perimeter |
| Touching boards without grounding | Failure of chips (modem, memory) | Use an antistatic bracelet |
Another common problem is that the tape gets damaged when you build it, so if you plan to use the phone further, replace it with a new one (you can buy it in Xiaomi remakes), and the old tape loses its adhesiveness when heated, and it doesn't keep it tight.
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The Redmi 7A’s main rule of disassembly is patience and accuracy, 80% of damage is due to haste or inappropriate tools.
Build: How to put everything back in place
The Redmi 7A is easier to disassemble, but there are nuances here:
- Make sure all plumes are tightly connected (especially the battery and fingerprint scanner).
- Check if there are any foreign objects (screws, scraps of tape) inside.
- Carefully place the lid in place, starting from the top (from the camera side).
- Press the perimeter lid so the latches fall into place, and a characteristic click will confirm the fixation.
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Before buying a lid, check its article! The Redmi 7A has two versions: the M1903C3GG (global) and the M1903C3GG (in India). They are identical in appearance, but may differ in the location of antenna lines.