Step-by-step dismantling of Xiaomi Redmi 3S: tools, nuances and repair tips

Xiaomi Redmi 3S is one of the most popular budget phones of 2016, but even it is not immune to breakdowns. If your gadget stops turning on, discharges in an hour or requires a replacement charging connector, disassembly can be the first step to repair. However, improper dismantling of the case often leads to damage to the plumes, disconnection of contacts or even failure of the motherboard.

In this article, you will find detailed instructions for disassembling the Redmi 3S, taking into account all the pitfalls from tool preparation to battery recovery. We will also tell you what mistakes beginners most often make, and give you tips on how to avoid damage. If you have never taken apart a smartphone, do not rush to take up a screwdriver: some steps require jewelry accuracy.

Preparation for disassembly: tools and security measures

Before you start, make sure you have everything you need. Xiaomi Redmi 3S is built on latches and glue, so you can't do without specialized tools. Here's the minimum set:

• 🔧 Plastic mediators (2-3 pieces) - for careful undersizing of the body.
• 🔨 The screwdriver. PH00 — rear-cover.
• 🧲 Magnetic mat or tray – so as not to lose small details.
• 🔥 Dryer or thermo-air station - to soften the glue under the battery.
• 📏 Suction - will help to raise the screen (if you need to replace it).

⚠️ Warning: Don't use metal tools to tamper with the body - they scratch plastic and can damage plumes.If you don't have plastic mediators, replace them with guitar mediators or a credit card (but act extremely carefully!).

Also prepare the workplace:

• 💡 Good lighting – preferably a table lamp with an increase.
• 🧹 Clean surface without garbage (it is better to cover the table with paper).
• ⚡ Turn off your smartphone and remove it. SIM-card with a memory card (if installed).

Removal of the back cover: where are the latches and screws hidden

The first step is to dismantle the back, and in Redmi 3S, it's mounted on 8 screws and a few latches around the perimeter.

1. Turn the smartphone down with the screen.
2. Unscrew all screws around the perimeter (they can be hidden under stickers - gently tuck them with a nail or a mediator).
3. Insert a plastic mediator into the gap between the lid and the case (start at the bottom edge where the charging connector is).
4. Carefully drive the mediator along the body, snapping the locks. Do not force - if the lid does not respond, check if all screws are twisted.

⚠️ Attention: At the top of the case, a fingerprint scanner plume is hidden under the lid (if your model is equipped with one). Do not pull the lid sharply upwards - first lift it 1-2 mm and move it to the side so that the plume does not break.

All 8 screws twisted | Mediator inserted in bottom edge |No sudden movements - only smooth snap |The fingerprint scanner plume is not stretched-->

If the lid is glued (for example, after previous repairs), warm it up with a hair dryer at a minimum temperature (not higher than 60 ° C) so that the glue softens. Do not use a building hair dryer - it is too powerful and can melt plastic.

Removing the battery: why it can not be “pulled”

The battery in the Redmi 3S is glued to the body with double-sided tape. Many beginners try to just pull it out, but this can damage the contacts or break the battery (which is dangerous to fire!).

1. Disconnect the battery plume from the motherboard (use a plastic mediator or tweezers).
2. Put the battery on any edge and pull it up. If it doesn't lend itself, warm up the body with a hairdryer (temperature: 50-60°C, distance: 5-10 cm).
3. Put a thin plastic card or mediator under the battery and carefully “cut” the glue as you move along the body.

Critically, if the battery is swelling (as seen from the deformation of the lid), do not try to remove it yourself - contact the service center. The risk of fire or rupture in this case is extremely high!

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If the battery is oxidized after the battery is removed, clean it with a cotton swab dipped in isopropyl alcohol, which will improve contact and prolong the life of the battery.

Dismantling the motherboard: where hidden "traps"

The Redmi 3S motherboard is mounted on multiple screws and connected to the body by multiple plumes, and the main difficulty is that they can be damaged if handled carelessly.

1. Unscrew all the screws fixing the board (they can be of different lengths - remember where it was!).
2. Disconnect the plumes in that order: 📱 Display plume (the widest, at the top of the board). 🔊 Dynamic plume. 📷 Camera plumes (rear and front). 🔋 Power/volume button plume.

Carefully raise the fee on one side and check if there are any unconnected plumes left.

⚠️ Attention: The power button plume is often glued to the board — don't pull it by force, but gently pull it with a mediator. If you break this plume, the buttons will stop working, and it will cost 30-50% of the cost of a smartphone to replace it.

If you're disassembling the Redmi 3S to replace the charging socket, you don't have to take the board out completely -- you just need to disconnect the battery and unfurl the old socket, but you need a soldering station and microelectronics experience.

Replacing the screen: when it is justified and when it is not

Redmi 3S screen is one of the most vulnerable parts of a smartphone, and if it has cracked or the sensor has stopped responding to touch, replacing it can bring the gadget back to life.

• 💰 The cost of a new screen is from 1,500 to 3,000 rubles (depending on the quality).
• ⚙️ Difficulty of replacement - it is required to disconnect the plumes, warm up the glue, exact installation.
• 📉 Market price of Redmi used 3S — 2,000 to 4,000 rubles. If it costs more to repair, it's easier to buy another smartphone.

If you do decide to change the screen, follow this algorithm:

1. Warm up the screen edge with a hair dryer (temperature - 60-70 ° C) for 2-3 minutes.
2. Subdue the screen with a plastic mediator, starting at the bottom edge (where the Home button is).
3. Carefully separate the screen from the body, making sure not to break the touch plume.
4. Disconnect the display and sensor plumes from the motherboard.
5. Install a new screen, plug in the plumes and check the operability before final assembly.

⚠️ Warning: When you install a new screen, remember to move the Home button (if it doesn't come with it) to it, without it, the touch button won't work, and the physical one will have to be purchased separately.

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Replacing the screen Redmi 3S is justified only if the cost of repair does not exceed 50% of the price of a new smartphone, otherwise it is more profitable to sell the device for spare parts and buy money to a more modern model.

Frequent Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling Xiaomi Redmi 3S. Here are the most common of them and ways to prevent them:

• 🔧 Loss of screws – use a magnetic mat or stick screws on the scotch in order of twisting.
• 🔥 Overheating when soldering – if soldering the charging connector, do not keep the soldering iron for longer than 3 seconds on one contact.
• 📱 Display plume damage – do not bend it at an angle of more than 90 degrees.
• 🔋 Short circuit – before assembly, inspect the board for metal dust or screw debris.

Another common problem is the power button that's broken after assembly, and most often it's because of:

• Incorrectly connected button plume.
• Getting dirt under the button (need to clean with alcohol).
• Damage to contacts on the board (solding is required).

If after disassembly the smartphone stopped charging, check:

1. Is the battery plume connected?
2. Integrity of the charging connector (contacts are often broken off when sloppy extraction).
3. The presence of voltage on the board (if there is no experience - contact the service).

When the disassembly will not help: signs of serious breakdowns

Not all Redmi 3S breakdowns can be repaired on their own, but here are the signs that disassembly is pointless or even dangerous:

• 💥 The smartphone does not turn on and does not respond to charging - perhaps the motherboard burned (diagnosis with a multimeter is required).
• 🔥 There was a smell of burning or smoke - a sign of a short circuit, further disassembly can aggravate the problem.
• 📡 No network or Wi-Fi – often associated with damage to antenna tracks (repair requires specialized equipment).
• 🔋 Battery swollen - disassembly is dangerous (risk of fire).

If you find at least one of these signs, it is better to contact a service center, for example, repairing the motherboard will cost 2,000-5,000 rubles, but it is cheaper than buying a new smartphone (if the Redmi 3S is dear to you as a backup device).

It is also worth refusing self-repair if:

• You have no experience with a soldering station (to replace connectors or chips).
• You are not sure about the cause of the breakdown (for example, the smartphone spontaneously turns off).
• The warranty is still valid (disassembly cancels it).

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If you've taken out the Redmi 3S and you find that the problem is bigger than it seemed, don't panic. Carefully put the phone back together (even if it doesn't work) and take it to the service, and it'll be easier for the wizards to diagnose the breakdown if all the parts are in place.

FAQ: Answers to Frequent Questions