Disassembly Xiaomi Mi A3: step-by-step guide with photos and nuances

Introduction: When and Why to Disassemble the Mi A3

The Xiaomi Mi A3, launched in 2019, is still popular with users due to its balanced specs and software support for Android One. However, over time, even reliable hardware requires repairs, from replacing the battery to cleaning the connectors or recovering from a fall.

This guide will help you disassemble the Xiaomi Mi A3 without damage if you are faced with one of the typical problems: fast battery discharge, a broken speaker, a dirty charging connector or a cracked camera glass. We will describe each step in detail, specify the necessary tools and warn against common errors. Importantly, the Mi A3 has a fragile fingerprint scanner plume - its damage leads to a complete loss of sensor functionality.

If you're not sure about your abilities, you should go to a service center, but for those who are willing to do it on their own, this article will be a reliable guide. Let's start with the preparation!

Preparation for disassembly: tools and precautions

Before you start disassembling the Xiaomi Mi A3, pack everything you need, and if you don't have the right tools or rush to do so, it can often damage the body, plumes, or even the motherboard.

• 🔧 Plastic blades (2-3 (a) - for the careful liding and disconnection of the plumes.
• 🔨 Cross screwdriver (PH00 or PH0) — hull-rotor.
• 🧲 Magnetic mat or container – to avoid losing small details.
• 🔥 Hair dryer or thermo-air station - for softening the glue (optional, but useful).
• 📸 Smartphone for photography - fix the location of plumes and screws.
• 🧴 Isopropyl alcohol (90%+) — clean-up.

Also, prepare the workplace: it should be clean, well-lit and without static electricity. SIM-If the battery is swelling, don't try to disassemble the device yourself!

⚠️ Attention: Disassembly Xiaomi Mi A3 If the phone is warranty-free, first contact an authorized service center.

Step 1: Removing the back cover - how not to break the latches

The back cover of the Mi A3 is mounted on latches and glue. To remove it, heat the body with a hairdryer around the perimeter for 1-2 minutes (temperature ~60 ° C). This will soften the glue and reduce the risk of damage.

1. Insert a plastic blade into the gap between the lid and the body at the charging connector.
2. Carefully drive the shoulder blade along the edge, alternately snapping the mounts.
3. When the lid starts to rise, don’t remove it completely – first unplug the fingerprint scanner plume (see next step).

A typical beginner mistake is to try to pull the lid off with a jerk, which causes cracks or a plume to break. If the lid doesn't respond, warm up the problem area again. On the Mi A3, the latches at the top (near the camera) are particularly vulnerable, where the plastic is thinner.

After removing the cover, you will see:

• 🔋 Battery with duct tape.
• 📱 Motherboard under metal screen.
• 🎤 Microphone and speaker at the bottom.
• 📸 Main camera module (three lenses).

Step 2: Disconnect the fingerprint scanner plume and battery

The first thing you need to do after you take off the lid is to turn off the battery.

1. Tap the black battery plume with a plastic spatula and gently disconnect it from the connector on the motherboard.
2. Secure the plume with tape so that it does not touch the contacts (this will prevent accidental circuit).

Now, let's take a fingerprint scanner plume, which is located under the lid, right next to the top of the battery, and this plume is extremely fragile, and it's damaged, causing the sensor to fail, so that you can disconnect it.

• 🔍 Find a white connector on the motherboard (signed as "FPC").
• 🖐️ Carefully pluck the plume on both sides and pull it parallel to the board (not upwards!).

⚠️ Note: If the fingerprint scanner is not working after assembly, the plume is likely damaged, in which case it will need to be replaced (article: MDY06-001-15P).

Step 3: Battery Removal – Risks and Nuances

The battery in the Mi A3 is glued to the body with double-sided tape to remove it.

1. Remove two adhesive tapes by pulling the black tongues (they are located under the battery).
2. If the tapes are broken, apply the battery with a plastic spatula, starting at the top edge.
3. Don’t use metal tools – they can puncture the battery!

Remove the bloated battery with extreme caution. If it is deformed, do not try to puncture or bend it, this can lead to fire.

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If the battery's adhesive tapes break, use isopropyl alcohol to dissolve the glue residues. New tape can be bought at radio parts stores (e.g. 3M 9448A).

Step 4: Access to the motherboard and other components

Once the battery is removed, you can start dismantling the motherboard.

1. Unscrew all the screws (there are 12 pieces, of different lengths – remember the location of each).
2. Disconnect the plumes: 📞 Display module (at the top of the board). 🔊 Speaker and microphone (bottom). 📷 Main camera plume (under metal screen).

Carefully tuck the board with a plastic spatula and remove it.

On the motherboard Mi A3 are located:

• 🧠 Snapdragon 665 processor (under metal radiator).
• 💾 EMMC memory 5.1 (64/128 GB).
• 📡 Modules. Wi-Fi/Bluetooth and NFC (top-right).

⚠️ Warning: Don't pull the screws when you build them, it can damage the board. Optimal effort: until you click.

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The most common mistake in disassembling the Mi A3 is screw confusion: screws of different lengths: short (2 mm) attach the screen, long (3 mm) attach the motherboard, and if you confuse them, you risk damaging the display or the board.

Step 5: Disassemble the front panel and display

If you need to replace the display, the charging connector or the front camera, you need to remove the front panel, which is the most difficult step, because the display is glued to the frame.

1. Heat the screen with a hair dryer (temperature ~70°C) around the perimeter for 3-5 minutes.
2. Insert a plastic blade into the gap between the display and the frame (start at the bottom edge).
3. Carefully drive the shoulder blade along the edge, separating the glue. Suction cups here will not help - the glass sits too firmly.
4. After separation of the display, disconnect the plumes: 📺 Main display plume. 📞 Sensory layer plume.

The Mi A3 often breaks the charging connector (USB-C). If the phone is not charging or is defined as an "unidentified device", the problem may be in it. Replacing the connector requires soldering work, but it can be purchased separately (article: XM-05K).

Typical problems after disassembly and their solution

Even with a careful disassembly, there can be problems, and here are the most common ways to fix them:

If the phone does not turn on after assembly, first check:

• 🔌 Battery connection (sometimes the plume is not fully inserted).
• 🔧 All screws (unwounded can cause a circuit).
• 📱 Contacts of the power button (it can stick after disassembly).

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If the battery is replaced after a few hours, check the battery consumption in the settings (Settings → Battery).

FAQ: Frequent questions about the dismantling of the Xiaomi Mi A3