How to open Xiaomi Mi A3: disassembly of the cover and access to the insides

Xiaomi Mi A3 is a popular smartphone with the Android One software platform, but even it has problems over time: a bloated battery, cracked camera glass or the need to clean the connectors. Disassembly of the device requires caution – improper actions can damage the plumes or display. In this article, you will find detailed instructions with the photo, a list of necessary tools and unique tips for preventing breakage when opening the rear cover.

The Mi A3 is different from Xiaomi's flagship models: there's no removable battery, and the lid is glued around the perimeter. This makes it difficult to access the insides, but with the right approach, the procedure will take no more than 20 minutes. We'll look at two methods, using a suction cup and a mediator, and an alternative method for cases where the glue is too strong. We'll focus on the risks of damaging the plume of the fingerprint scanner, which often suffers from careless disassembly.

Preparation for disassembly: tools and security measures

Before you open the Xiaomi Mi A3, prepare your workspace. Use a soft substrate (like a silicone mat or folded towel) to avoid scratching the glass. Lighting should be bright — use a desk lamp or flashlight. Here is the full list of tools:

• 🔧 Plastic mediator (or guitar mediator) – to separate the cover and body.
• 🧲 Suction cup (diameter 4-5 cm) - helps to lift the lid after heating.
• 🔥 Hair dryer or thermo-air station - for softening the glue (temperature not higher than 60)°C!).
• 🔩 Screwdriver. T3 and T5 — screw-off.
• 🧴 Isopropyl alcohol (90%+) — glue-cleaner.
• 📦 Container for screws - so as not to lose small details.

⚠️ Warning: Don't use metal tools (knives, screwdrivers) to lid the lid! They will damage the plastic case and may catch the plumes. If you don't have a suction cup, replace it with wide tape, gluing it to the lid to grab it.

Also, prepare spare parts if you are planning a replacement:

• 🔋 New battery (original articulum: MB-J19).
• 📸 Rear camera (module) GC8034 + S5KGM1).
• 🖥️ Sticking glue to the cover (e.g, B7000).

Method 1: Opening the lid with a suction cup and a mediator

This is the safest way for most users, and follow the instructions Step-by-step:

1. Turn off your smartphone and remove it. SIM-scatter-card.
2. Heat the edges of the body with a hair dryer for 2-3 minutes, keeping it at a distance of 5-7 cm.
3. Attach the suction cup to the bottom of the lid (near the USB-C connector). Press to create a vacuum.
4. Pull the sucker up with moderate effort - a small gap should appear.
5. Put the mediator in the gap and gently run it along the edge, separating the lid. Start at the bottom and move counterclockwise.

Critical moments:

• 🛑 Don’t pull the lid sharply – the fingerprint scanner plume passes under it (FPC).
• 🔄 If the lid fails, heat the problem area again.
• 🧩 After the lid is separated, do not lift it completely - it is connected by a plume!

⚠️ Warning: If the glue is too sticky after heating, use thread or dental floss between the lid and the body, a method that requires patience but minimizes the risk of damage.

Method 2: Alternative method without suction (for experienced)

If you don't have a suction cup, you can do with a plastic card and a tape, and this is a method that requires more care.

1. Stick a wide scotch onto the back cover of the cross, leaving loose edges for grabbing.
2. Heat the body with a hair dryer, as in the first method.
3. Pull the scotch up while putting the edge on with a plastic card.
4. Once a gap appears, insert the mediator and continue the separation.

This method is suitable for Mi A3 with already weakened glue (for example, after previous disassemblies).

Screwing and removal of plumes

When the lid is separated, you'll see 10 different sized screws. It's important not to confuse them when you reassemble them!

After the screws are unscrewed:

1. Gently disconnect the battery plume (use plastic tweezers).
2. Remove the metal protection of the motherboard (twisted with 4 T3 screws).
3. Disconnect the plumes: display, fingerprint scanner, main camera.

⚠️ Attention: Fingerprint scanner plume (FPC) If it's damaged, the touch-id will stop working. If you're not planning to replace the display, don't unplug the plume without having to.

💡

Before you disconnect the plumes, take a picture of their location on your phone, which will help you connect everything back together correctly, especially if you're a beginner.

Frequent Mistakes and How to Avoid Them

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

• 🔋 Damage to the battery when you try to remove it. Never hit the battery with sharp objects! Use a plastic blade and heat the glue under the battery.
• 📱 Cracked display due to excessive pressure on the cover. If the cover doesn't lend itself, heat it again instead of pulling it harder.
• 🔌 The charging plume breaks, right next to the USB-C port and often suffers from careless opening.
• 🧲 Loss of screws. Use a magnetic mat or a cell container to sort.

If you notice that after assembly, the vibration is not working or the battery is not charging, most likely the problem is in the wrong plugs.

💡

The main rule of disassembling the Mi A3 is not to rush. 80% of breakdowns occur due to an attempt to speed up the process.Heating, neat separation of the lid and consistent unscrewing of the screws will save you time for repairs.

Reverse Assembly: Tips for Fixing the Cover

Once the repair is complete, the back cover must be securely secured, and the Mi A3 uses double-sided adhesive, which loses its properties after the first opening.

• 🔥 Use the original adhesive (e.g. Xiaomi Adhesive Strips for Mi) A3). It provides tightness and protection from dust.
• 🧴 Apply liquid glue (for example, B7000) Apply a thin layer to avoid hitting the speaker and microphone.
• 📦 Interim Solution – Bilateral Scotch (3M VHB). Suitable for testing, but not for permanent use.

When assembly, make sure that:

• All the plumes were connected before the lid was fixed.
• The screws were twisted with the right effort (do not pull!).
• The cover fits tightly around the perimeter (check the gaps).

⚠️ Warning: If the smartphone doesn't turn on after assembly, check the battery plume and power button connection. Often the reason lies in a leaky contact.

FAQ: Answers to Frequent Questions