Xiaomi Redmi Note 9 Pro is one of the most popular smartphones in the budget segment, but even it is not immune to moisture. If your device fell into water, fell in the rain or condensed inside the case, the only way to save the device is to disassemble it as quickly as possible and dry it. However, improper disassembly can cause even more damage from damage to plumes to short circuit on the board.
In this article, you will find a step-by-step photo guide, a list of tools you need, and critical warnings to help avoid errors. We will discuss how to remove the back cover without damage, turn off the battery, remove the motherboard and other components, and also tell you which drying methods really work and which myths (for example, about rice).
Preparation for disassembly: tools and security measures
Before you start disassembling the Redmi Note 9 Pro, make sure you have everything you need. The absence of even one tool can damage the body or internal components.
- 🔧 Set of screwdrivers (cross-haul) PH00, flat 1.5 mm, five-pointed Y00 rivet-rotor).
- 🧲 Suction (to remove the back cover) or plastic mediator.
- 🔥 Hair dryer with temperature adjustment (maximum 50-60)°C!).
- 📦 Silicagel container (or specialised packages for moisture absorption).
- 🧴 Isopropyl alcohol 99% (to clean the board from corrosion).
- 📸 Smartphone for photography (to capture the location of screws and plumes).
Important: Do not use metal tools (knives, screwdrivers with sharp edges) to slap the lid, this will lead to scratches or cracks. Also avoid WD-40 or other lubricants: they can damage seals and rubber gaskets.
⚠️ Attention! If your smartphone has been submerged in salt water (sea, ocean), immediately rinse the board with distilled water before drying!
Step 1: Turn off and remove the battery
The first and most critical step is to turn off the power completely, and even if the smartphone doesn't respond to the buttons, it doesn't mean there's no voltage on the board.
- Hold the power button for 10-15 seconds to force the device to turn off.
- If the screen doesn’t respond, don’t try to charge the smartphone – it can cause a short circuit.
- Remove the back cover (instructions in the next section) and disconnect the battery plume first.
In the Redmi Note 9 Pro, the battery is mounted on double-sided tape, but don't try to tear it off by force -- put a plastic blade on the side where there are no components. If the battery is swelling, don't pierce it or heat it up -- it can cause fire.
Turn off the smartphone forcibly
Remove the back cover
Disconnect the battery plume (extreme connector on the right)
Check for no battery bloating
Photograph the location of the screws-->
Step 2: Removing the back cover – hidden screws and traps
The Redmi Note 9 Pro back cover is mounted on 12 screws (including those hidden under the stickers!) and adhesive layer. Here's how to remove it without damage:
- Heat the edges of the cover with a hair dryer (40–50°C) for 1-2 minutes to soften the glue.
- Tap the lid with a plastic mediator or suction cup from the bottom edge (near the USB-C connector).
- Carefully swipe the mediator around the perimeter, separating the lid. Do not use force - if the lid does not respond, warm up again.
Features of this model:
- 🔍 Two screws are hidden under stickers near the camera and under the tray for SIM-map.
- 🚫 Do not use metal tools – the aluminum case is easy to scratch.
- 📱 The cover is connected to the fingerprint scanner plume – do not pull it sharply!
| Component | Number of screws | Type of screwdriver. | Notes |
|---|---|---|---|
| Back cover. | 12 (including hidden) | PH00, Y00 | 2 screws under the stickers |
| Battery | — | — | Scotch-stained. |
| Maternity fee | 8 | PH00 | Rotors of different lengths! |
| Camera. | 3 | PH00 | The plume is fragile - do not bend |
⚠️ If you see white or green spots on the board after you remove the lid, it's corrosion. Clean them immediately with isopropyl alcohol and a brush, or the damage will become irreversible within 24 hours.
What to do if the screw breaks?
Step 3: Removing the motherboard and other components
After removing the lid and turning off the battery, you can start removing the board. In the Redmi Note 9 Pro, it is mounted on 8 screws, but there are nuances:
- 🔧 The screws are of different lengths – remember which one is from, or take a picture.
- 📶 Antenna plumes (for Wi-Fi and NFC) Easy to pull off - unplug them last.
- 🔊 The speaker and vibrator are attached separately - do not pull the board until they are turned off.
Procedure:
- Unscrew all the screws of the board (start with the corners).
- Disconnect the plumes in this order: screen → camera → power button → antennas.
- Carefully raise the cost for the edges. If it's stuck, check if you've forgotten the screw.
Don't touch chips with your bare hands -- static electricity can damage them. Use an antistatic bracelet or at least touch a grounded metal object before work.
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If the board doesn't detach, check the USB-C connector -- sometimes it sticks to the case because of oxidation. Carefully tuck it in with a plastic spatula.
Step 4: Drying Components – What You Can and Can’t Do
Now that all the ingredients are extracted, you have to dry them, and the most common mistake is to use rice or salt or other folk methods, which are not only inefficient, but also dangerous: rice particles can get into the connectors, and salt will accelerate corrosion.
The correct drying methods:
- 🌬️ Fan at minimum speed (direct air flow to the board from a distance of 20-30 cm).
- 💧 Silicagel (place components in a sealed container with bags for 24-48 hours).
- 🔥 Hair dryer at low temperature (40–50)°C, no higher!) Keep 10 cm away, moving constantly.
What can't be done:
- ❌ Dry on a battery or under direct sunlight (overheating will damage the fee).
- ❌ Use a vacuum cleaner (static electricity kills chips).
- ❌ Immerse the board in alcohol (only wipe with a brush!).
| Drying method | Time. | Efficiency | Risks. |
|---|---|---|---|
| silicagel | 24-48 hours | ⭐⭐⭐⭐⭐ | No. |
| Fryer (40-50°C) | 1-2 hours | ⭐⭐⭐⭐ | Overheating in case of non-compliance with temperature |
| Fan | 6-12 hours | ⭐⭐⭐ | Dust could hit the board |
| Rhys | 48+ hours | ⭐ | Rice particles, corrosion |
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Even if the smartphone is turned on after drying, during the week, "delayed" problems can appear: overheating, spontaneous reboots, a broken camera. These are signs of hidden corrosion - redisassembly and cleaning with alcohol are required.
Step 5: Build a smartphone and check the health
After drying, start the assembly. Follow the reverse order, but keep in mind:
- 🔧 Check if all screws are in place - an "extra" screw inside the body can cause a short circuit.
- 📶 Make sure all plumes are tightly connected (especially antenna and screen plume).
- 🔋 The battery should lie flat, without gaps - otherwise it will warm up.
Before final assembly:
- Connect only the battery and check if the smartphone is turned on.
- If the screen is not responding, check the display plume.
- If the device warms up or discharges quickly, the board is most likely damaged.
⚠️ If the smartphone doesn't turn on after assembly, don't plug it into charging, it could burn the power controller.
Frequent Mistakes and How to Avoid Them
Even experienced users make mistakes when disassembling the Redmi Note 9 Pro. Here are the most common:
- 🔨 Use of inappropriate screwdrivers - five-pointed screws (Y00) often tore off with a cross screwdriver.
- 💦 Drying without board removal - moisture remains under the screen and corrodes the plumes.
- 🔥 Overheating by a hair dryer - temperature above 60°C deforms plastic parts.
- 📱 Sharp disconnection of plumes - they are fastened by latches, which must be opened beforehand.
If you doubt your abilities, it is better to contact the service. The cost of repairs after an unsuccessful self-disassembly often exceeds the price of a new smartphone.
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Before assembly, wipe the battery and board contacts with a brush (normal school) to remove oxides and improve contact.