Disassembly Xiaomi Mi A3: safe dismantling of the body and components

The Xiaomi Mi A3 is a popular smartphone with Android One software platform, but even it can have hardware problems over time, from a dead battery to a faulty speaker. Disassembling the device requires accuracy and knowledge of the design features of the model. Unlike the flagship Mi or Redmi with metal cases, the Mi A3 has a plastic rear panel, which makes it easier to access the insides, but hides its pitfalls.

This guide will help you disassemble your phone without damage, even if you're doing it for the first time. We'll take a closer look at what tools you need, how to remove the lid, turn off the battery, and remove key modules. We'll focus on mounting the fingerprint scanner plume, which is easily damaged when you move carelessly, and you'll learn what mistakes beginners most often make and how to avoid them.

Preparation for disassembly: tools and security measures

Before you start, make sure you have everything you need. Xiaomi Mi A3 does not require professional equipment, but without special tools, the risk of damage to the case or plumes increases significantly.

• 🔧 Plastic mediators (2-3 (a) - for separation of the body without scratches
• 🔨 The screwdriver. PH00 — motherboard-mounting screw
• 🧲 Magnetic mat or screw container – to avoid losing small details
• 🔋 Suction (optional) - helps to lift the back cover
• 📸 Smartphone for photography – fix the location of the plumes before disconnecting

Important: The Mi A3 has a battery adhesive mount, so it may need isopropyl alcohol (90%+) or a special battery suction tool to extract it. Don't use metal objects - they can puncture the battery!

⚠️ Warning: If the phone has been in water or has been hit hard, disassembly may result in a short circuit.In such cases, dry the device completely in rice or silica gel for at least 48 hours.

Step 1: Removing the back cover

The back of the Xiaomi Mi A3 is mounted on latches and glue. Start by heating the body around the perimeter with a hairdryer (temperature no higher than 60°C) and this will soften the glue.

1. Insert a plastic mediator into the gap between the lid and the frame next to the power button.
2. Carefully drive the mediator along the housing, gradually lifting the lid. Do not force - if the latch does not respond, heat the place again.
3. After the lid is separated along the perimeter, remove it, starting from the bottom (where the USB-C connector is located).

Under the lid, you'll see:

• 🔋 Battery with black protective film
• 📱 Motherboard under metal screen
• 🔊 Dynamic and vibrator at the bottom
• 📸 Triple camera module with flexible plume

Step 2: Shutting off the battery

First rule of disassembly: always turn off the battery before working with the internal components. In the Mi A3, the battery connector is located at the top of the board and closed with a black protective cap.

1. Put the connector cap on a plastic tool and remove it.
2. Carefully pick up the battery plume behind the plastic "tongue" and pull it from the connector vertically up.

If the plume fails, don't pull it with force, check if it's caught on nearby components. After the battery is turned off, wait 1-2 minutes for the residual capacitors on the board to run out.

⚠️ Warning: If you see a battery bloating (the lid is raised in the center), do not try to remove it yourself! Bloated batteries are prone to spontaneous combustion.

Step 3: Removing the motherboard

The Mi A3 motherboard is mounted on 8 screws (PH00 size) and several latches, and all plumes must be turned off before removing it:

Once the plumes are turned off, unscrew all the screws and gently raise the charge with a plastic blade. Start at the USB-C connector side, there's less risk of catching flexible cables. If the board fails, check if there are any undetected mounts.

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Take a picture of the screws' location before extraction - they may vary in length! putting a long screw in an undesignated location will damage the board.

Step 4: Dismantling the battery

The battery in the Mi A3 is glued to the body, and it's the most critical step to take it out.

• 🧴 Isopropyl alcohol (90%+) — glue-dissolving
• 📄 Plastic card or mediator - for tampering with the battery
• 🧊 Cold air (optional) – to cool the battery after heating

Instructions for extraction:

1. Apply alcohol on the edge of the battery and wait 2-3 minutes.
2. Carefully tuck the battery with a plastic tool, starting from the top corner.
3. If the battery is not going away, add alcohol and try again.
4. After extraction, clean the body of glue residues with alcohol.

⚠️ Warning: If the battery is deformed or has signs of corrosion, do not attempt to restore it. Dispose of the old battery according to local regulations (at electronics reception points).

Common Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling the Xiaomi Mi A3, and here are the most common ones and ways to prevent them:

• 🔧 Shooting screws - use a magnetic-tipped screwdriver and don't use too much force. If the screw doesn't go, try dripping. WD-40.
• 📸 Camera plume damage - always turn off the plumes by pulling on the plastic tongue, not the wires.
• 🔋 Puncture of the battery - never use sharp objects to remove it. If the battery is swelling, contact the service.
• 🧲 Loss of screws – use a magnetic mat or cell container to sort.

Another common problem is that antenna lines get damaged when you uncook the motherboard, and these thin copper tracks are located on the edges of the board, and they break easily, and if you lose LTE or Wi-Fi after assembly, that's probably the fault.

1. Correct connection of the battery

Integrity of the feed plume

3. No circuits on the board (visually)

In 90% of cases, the problem lies in one of these points.-->

Building a phone: the reverse order of action

To assemble Xiaomi Mi A3 need in reverse order, but taking into account a few nuances:

1. Before installing the battery, clean the contacts on the board and battery with an alcohol tampon.
2. New battery glue apply only to the edges - the center should remain free for heat removal.
3. When you connect the plumes, make sure the latches are secure, and check this with a slight twitch.
4. Screw the screws cross-curl to avoid skewing the board.

Don't turn the phone on immediately after assembly. First, plug the charger in and wait for the charge indicator to appear, and if it doesn't light up, turn off the battery and check all connections again.

To check the availability:

• 📞 Call the phone – check the microphone and speaker
• 📸 Take a photo on the front and main cameras
• 🔋 Make sure the charging is stable (without overheating)
• 🌐 Connect to Wi-Fi and mobile network

FAQ: Frequent questions about the dismantling of Xiaomi Mi A3