How to gently open the back cover Xiaomi Redmi 9: instructions with photos and warnings

The back cover of Xiaomi Redmi 9 is not only attached to the latches, but also on the adhesive layer, which makes it difficult to remove it without damage. Many users face the need to disassemble the device for battery replacement, dust cleaning or plume repair, but are afraid of damaging the case or display. In this article, we will analyze three officially approved methods for opening the lid, list the necessary tools and reveal the secret technique for models with reinforced ad adhesive (reinafter Redmi 9 after restyling 2021).

It is important to understand: even with a careful removal of the lid, you lose the factory tightness (IP-The manufacturer does not recommend self-review, but if you decide to follow our recommendations to minimize risks, we will also tell you how to check the integrity of sealing rubber bands after assembly and what to do if the lid does not fit back tightly.

Preparation for analysis: tools and conditions

Before you start removing the lid, make sure you have everything you need, and not even one tool can cause plastic to chip or damage to the battery plume.

• 🔧 Plastic mediators (2-3 pc, thickness 0.1–0.2 mm) to separate the cover and the shell
• 🔥 A building (or powerful household) hair dryer – to soften glue
• 🧲 Suction (diameter 3-5 cm) - for the initial lid suction
• 📏 Plastic card or guitar mediator as an alternative to specialized instruments
• 🧴 Isopropyl alcohol 90%+ — glue-cleaner
• 🔋 New adhesive layer (optional if you plan to reassemble the device)

Also prepare the workplace: a table with a soft substrate (for example, a towel), good lighting and a screw container (if you take off the motherboard). The temperature in the room should be at least 20 ° C - cold glue is harder to separate.

⚠️ Warning: Do not use metal screwdrivers or knives to lid the lid! Even a little pressure can puncture the battery or damage the flexible plumes under the lid. 80% of the damage to the disassembly is the fault of the wrong tool.

Method 1: Classical Mediator Removal (for most Redmi 9s)

This method is suitable for the Redmi 9 standard build (models M2003J15SC, M2003J15SS).It involves neat separation of the cover without heavy heating, which reduces the risk of damage to internal components.

1. Turn off the phone and remove it. SIM-The battery must be at least 30 percent charged, which will prevent accidental switching on during disassembly.
2. Plug paint tape on the display along the edge of the lid – this will protect the glass if the mediator slips.
3. Place the suction cup to the lower left corner (where the tray notch is located). SIM-And pull it up a little bit, and then you put a plastic pickup in the gap.
4. Carefully drive the mediator along the edge, separating the latches. Redmi 9 has 12 plastic latches: 4 on the long sides and 2 on the upper / lower end.

If the lid doesn't lend itself, don't force it! Probably the glue is too strong, go to the heating method.

Method 2: Preheating removal (for models with reinforced glue)

This method is mandatory for the Redmi 9 after restyling in 2021 (modifications with the G suffix in the model number, for example, M2003J15SG).The manufacturer has strengthened the adhesive layer to improve dust protection, so the cold compartment of the lid almost always ends in cracks.

Algorithm of action:

1. Heat the hair dryer back cover around the perimeter for 2-3 minutes, keeping it at a distance of 5-7 cm The air temperature should be 60-70 ° C (not higher!).
2. While the cover is warm, repeat the steps from the first method, but with a force of 30% less - softened glue goes away easier.
3. If the lid is not fully removed, heat the problem areas again and try again.

⚠️ Attention: Overheating over 80°C can warp plastic cover or damage lithium polymer battery.Use an infrared thermometer to monitor temperature if in doubt.

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If you don’t have a hair dryer at hand, use hot water in the bag: pour 60°C water into a zip bag, apply it to the lid for 1-2 minutes. The effect will be weaker, but the glue will soften.

Method 3: Alternative threading method (for power users)

This method requires skill, but allows you to remove the lid with minimal risk of damage to the latch. Suitable for all versions of the Redmi 9, including the Redmi 9A and Redmi 9C.

• 🧵 Strong nylon thread (e.g. line with a diameter of 0.3 mm)
• 🔧 Two plastic mediators
• 🧲 Suction cup.

Instructions:

1. With the help of a suction cup, slightly lift the lid in any corner and insert the end of the thread folded twice into the slot.
2. Stretching the thread along the perimeter, like a "saw" glue. Hold the thread at an angle of 45.° case-wise.
3. In places of the latch, help with the mediator, gently pressing the lid from above.

The advantage of the method is that the thread evenly cuts the glue, leaving no traces on the plastic, and the disadvantage is that it takes longer (10-15 minutes versus 3-5 minutes for the classical method).

Common Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when parsing Redmi 9, and here are the most common ones and ways to prevent them:

• 🔋 Battery plume damage occurs when the lid is overbending. Solution: Separate the lid no more than 2-3 mm at a time until you disconnect all latches.
• 🔥 Battery overheating - if you heat the dryer for longer than 3 minutes Solution: Take 1 minute breaks every 2 minutes of heating.
• 📱 Cracks on the display due to mediator pressure. Solution: Use a screen protector or paint tape.
• 🔌 Break antenna contacts - if you pull the lid on the upper end. Solution: Start separation from the lower left corner (at the tray). SIM).

If you do damage the plume or contact, don't panic. Redmi 9 is the most vulnerable.

• Display module plume (cost of replacement: 1,200–1,800) ₽)
• Contacts NFC-antennas (if they are detached, the module will stop working)
• Flexible side button cable (repair costs 800-1 200) ₽)

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The most common breakdown in disassembly is a fracture in the tailpipe of the rear chamber, which attaches to the lid with two points of glue and easily detachs when you move sloppy, and always check its integrity after the lid is removed!

What to do after the lid is removed?

When the lid is finally separated, don't rush to start repairing.

1. Check the perimeter sealing rubber gaskets. If they are torn or deformed, replace them before assembly.
2. Check the integrity of the adhesive layer. If it's still on the lid, remove it with isopropyl alcohol.
3. Disconnect the battery (if you plan to work with the motherboard), and then put a plastic blade on the connector.
4. Take a picture of the location of all the plumes and screws - this will help with the reverse assembly.

If you have removed the battery cover, consider: the new battery for Redmi 9 should have a capacity of 5020 mAh and support fast charging 18W. Buy only original batteries (article: MB-J10B) or certified analogues from ATL or Sunwoda.

How to reassemble your phone without losing functionality?

Building the Redmi 9 after repair is as much a process as disassembling.

• 🔧 Rotate the screws in reverse. Redmi 9 uses three types of screws: Phillips #00 (motherboard) Tri-wing Y00 (for camera attachment) Flat-head 1.5mm (tray SIM)
• 🧲 Apply the adhesive layer in a thin layer (no more than 0.1 mm thick). Use bilateral tape 3M 9448A liquid-glue B-7000.
• 📶 Test the antenna contacts with a multimeter for integrity before final assembly.

After assembly, be sure to test:

• Operating of the cameras (front and main)
• Sensitivity of the touch screen
• NFC function (if any)
• Battery charging and discharge

⚠️ Warning: If the phone doesn't turn on after assembly, but it vibrates when connected to charging, the power plume is a problem. It can be temporarily pressed with tape, but it will require soldering to repair it.

FAQ: Frequent questions about the Xiaomi Redmi 9