Xiaomi Redmi Note 9S is one of the most popular smartphones of 2020, but even it is not immune to breakdowns. A cracked screen, a swollen battery, or a faulty speaker are all problems that require disassembling the device. However incorrect dismantling can lead to damage to cables, detachment of contacts, or even complete failure of the phone.

In this article you will find step-by-step disassembly instructions taking into account the design features Redmi Note 9S, including hidden latches, fragile elements and common beginner mistakes. We will also tell you what tools are required, and which ones you can do without, and we will give advice on diagnosing faults even before opening the case. If you have never disassembled smartphones, this guide will help you avoid fatal mistakes.

Preparing for Disassembly: Tools and Safety Precautions

Before you begin, make sure you have everything you need. Redmi Note 9S has adhesive back cover design and fragile cables, so a regular screwdriver will not be enough. Here is the minimum set:

  • 🔧 Plastic picks (2–3 pcs.) - to separate the case without scratches.
  • 🔨 Phillips screwdriver PH00 - for screws inside the device.
  • 🔥 Hair dryer or hot air station — to soften the glue (temperature 60–80°C).
  • 🧲 Magnetic mat or container - so as not to lose the screws.
  • 📱 Sucker — for the initial prying of the lid.
  • 🔍 Magnifier or magnifying glass - for inspection of small parts.

Important: Redmi Note 9S has hidden latch under the SIM card tray — it is easy to break if you pull the cover from this side. The device also uses 3M double sided tape, which, if removed carelessly, can leave marks on the frame.

⚠️ Attention: If you are disassembling a phone with a swollen battery, do not use metal tools - risk of short circuit and fire! In this case, it is better to contact the service.
📊 Have you ever disassembled a smartphone yourself?
  • Yes, repeatedly
  • Yes, but only the screen
  • No, I'm afraid to break it
  • Tried it but no luck

Removing the back cover: step-by-step instructions with photos

Let's start with the most difficult stage - separating the back panel. B Redmi Note 9S it is glued around the perimeter and is also fixed plastic latches near the buttons and camera. Here's how to do it without causing damage:

  1. Turn off your phone and remove the SIM card tray.
  2. Heat the edges of the case hairdryer (do not direct the air stream at the screen!). Start at the bottom where the USB-C connector is located.
  3. Use a suction cup to lift the lid at the charging connector and gently pull up. If the lid does not budge, heat it again.
  4. Insert a pick into the gap formed and move it along the body, separating the glue. Be careful in the area volume buttons — there are fragile latches located there.

If the cover is removed, but glue remains, do not tear it off by force. Better clean residues with isopropyl alcohol (70% and above). Inside you will see:

  • 🔋 Battery with flexible cable (don't pull on it!).
  • 📷 Main camera module (4 lenses).
  • 🔊 Speaker and microphone at the bottom.
  • 📶 Antenna contacts around the perimeter.

☑️ What to check after removing the cover

Done: 0 / 4

At this stage, many people make the mistake of trying to immediately disconnect the battery. First you need to unscrew the screws on the metal plate covering the motherboard!

Disconnecting the battery and removing the motherboard

Battery in Redmi Note 9S - one of the most vulnerable places. His the cable is soldered to the board, and the block itself is secured with double-sided tape. To avoid short circuit:

  1. Unscrew 5 screws on a metal plate (they are different sizes - remember the location!).
  2. Carefully pry the plate and remove it. Hidden underneath battery cable.
  3. Use plastic tweezersto disconnect the battery connector. Don't pull the wires!
  4. If the battery is swollen - don't pierce it. Wrap the phone in foil and take it to service.

Now you can start working on the motherboard. It is attached to 12 screws (including those under the stickers!). Pay special attention to:

  • 🔌 Charging connector — its cable often comes off during careless dismantling.
  • 🎤 Microphone and speaker - they are glued to the board.
  • 📡 Antenna contacts - they are easy to bend.
element Number of screws Screwdriver type Notes
Metal plate 5 PH00 Screws of different lengths
Motherboard 12 PH00, Y00 2 screws under stickers
Camera 3 PH00 Don't overtighten!
Battery — — Glue + cable
⚠️ Attention: If you are disassembling your phone after a fall, check integrity of the screen cable before removing the board. Often damage is only visible when switched on!
💡

Before unscrewing the screws, take a photo of their location on the board - this will simplify reassembly and prevent “extra” parts.

Screen replacement: nuances and common mistakes

Screen Redmi Note 9S - this is glued module (display + sensor + frame), so it is impossible to replace only the glass. When purchasing a new screen, pay attention to:

  • 📱 Screen model - the original ones are marked Tianma or BOE.
  • 🔧 Presence of frame — some kits are delivered without it.
  • 🎨 Color rendition - cheap analogues often have a cold tint.

Replacement process:

  1. Remove the back cover and disconnect the battery (as described above).
  2. Unscrew the screws securing metal plate above the screen cable.
  3. Carefully disconnect the cable display And sensor (they are different!).
  4. Heat the screen with a hairdryer (temperature 70°C) and pry it off plastic spatula from any angle.

In 80% of cases, screen damage is accompanied by tearing off the sensor cable — check its integrity before installing a new module. If the cable is torn, the entire display module will need to be replaced.

How to check the functionality of a new screen before assembly?

Connect the cables to the board and temporarily secure the screen with tape. Turn on your phone (holding the power button for 10-15 seconds). If there is an image, but the sensor does not work, the problem is in the cable or controller.

Troubleshooting: what you can fix yourself

Not every breakdown requires replacement of parts. Sometimes it's enough cleaning contacts or reconnecting loops. Here is a list of problems that can be fixed at home:

Symptom Possible reason Solution
Not charging Oxidation of the USB-C connector Alcohol cleaning + port replacement
Speaker doesn't work The cable is disconnected Reconnect the connector on the board
Spontaneous touches Damage to the screen cable Replacing a cable or screen
Doesn't turn on Battery discharge below 3% Charging via frog (5–10 minutes)

If the phone won't turn on after falling, first check:

  1. Integrity power cable (goes from the power button to the board).
  2. Presence of voltage on the battery (with a multimeter).
  3. Charging connector contacts - often come off on impact.
⚠️ Attention: If after assembly the phone overheats or discharges quickly, most likely you forgot to connect battery cable or damaged it. Turn off the device immediately!
💡

Most "malfunctions" after disassembly are associated with poor contact of the cables. Always check that the connectors are secure before final assembly.

Assembling a phone: how not to forget anything important

Collect Redmi Note 9S back is often more difficult than taking it apart. Main rules:

  • 🔩 Screws tighten in reverse order. Long screws in short holes = board damage.
  • 🧲 Loops connect before the board is fixed - this makes it more convenient to check the contact tightness.
  • 🔋 Battery glue with new double-sided tape (for example, 3M 9448A).
  • 📶 Antenna contacts must fit tightly to the frame - otherwise the signal will deteriorate.

Before final assembly:

  1. Check your work all buttons (volume, power).
  2. Connect the charger - the phone should recognize the cable.
  3. Test sensor, camera and speaker.

If something doesn't work, don't panic. Go back to the appropriate section and check:

  • 🔌 Are all cables connected?
  • 🔩 Have you forgotten the screws?
  • 📱 Are there any foreign objects inside (for example, fragments of a pick)?

Frequently asked questions about disassembly Redmi Note 9S

Is it possible to replace only the screen glass without changing the entire module?

No. B Redmi Note 9S glass is glued to the display and sensor (technology OGS). An attempt to separate the glass will damage the matrix. The only option is to replace the entire module.

What glue should I use for the battery?

The best option is double-sided tape 3M 9448A or similar with high adhesiveness. Do not use superglue or hot glue - they may damage the battery during future disassembly.

The phone does not turn on after replacing the screen. What's the matter?

Probable reasons:

  1. Not connected display cable or sensor.
  2. Damaged power cable (comes from the power button).
  3. The battery is discharged below 3% - try charging through the frog.

Check all connectors and try turning on the phone without the back cover.

Is it possible to disassemble Redmi Note 9S without a hairdryer?

Technically yes, but the risk of damage to the cover or cables increases significantly. The adhesive in this phone is very strong. Alternatives:

  • Use isopropyl alcohol to soften the glue.
  • Heat the lid hot water in a bag (risky!).
  • Contact the service - some workshops remove covers for 300–500 rubles.
Where to buy spare parts for Redmi Note 9S?

Reliable sources:

  • 🛒 AliExpress — original screens (look for sellers with a rating of 98%+).
  • 🏬 Local service centers - often sell used parts.
  • 🌍 Sites like Fixez or iFixit — there are diagrams and catalogs.

Cost of a new screen: 3,000–5,000 rubles, battery — 800–1,500 rubles.