How to gently open the case Xiaomi Redmi 3: tools, step-by-step analysis and warnings

Xiaomi Redmi 3 (including Redmi 3 Pro and Redmi 3S Prime) remains a popular device due to reliability and maintainability. However, disassembling the case is a task that requires caution: improper actions can damage the plumes, chips on the rear panel or even battery failure, this guide will help avoid typical errors and carry out dismantling without consequences for the gadget.

Unlike today's glue-enabled smartphones, Redmi 3 is relatively simple but has its own nuances: For example, plastic latches on the middle frame often break when exposed to rough, and the flexible plume of the fingerprint scanner (in models with fingerprint sensors) is easily damaged when the back cover is sloppy lifted, and we will examine each step in detail, from tool preparation to final assembly.

If you are planning to replace the battery, speaker or microphone, please note: after opening the case, the Xiaomi warranty is automatically canceled. NFC-A module (e.g. Redmi 3 Pro) will require extra care – the wireless charging antenna is integrated into the back cover and can come off when abruptly moving.

Preparation: Tools and Conditions for Safe Disassembly

Before you start dismantling, make sure you have everything you need. The minimum toolkit includes:

• 🔧 Plastic mediator (or guitar) - to disconnect the latches without scratches.
• 🔨 The screwdriver. PH00 (magnetic preferable) - for screws of the back cover.
• 🧲 Suction cup (3-4 cm in diameter) - will help to suction the screen if you need to remove it.
• 🔥 Dryer or thermoair station - for softening the glue (relevant when replacing the display).
• 📦 Container for screws - so as not to lose small parts (in Redmi 3 there are 12 pieces!).

Work on a flat, well-lit surface, and a white tablecloth is perfect (contrast will help you spot the screws that have fallen out). SIM-If the battery is swelling, don't try to disassemble the device yourself: the risk of lithium polymer battery fire is extremely high.

⚠️ Warning: If the phone has been in water, dry it in rice or silica gel for at least 48 hours before disassembling. Humidity inside the case can cause short circuits when in contact with tools.

Redmi 3S Prime models with metal back panels will require a more powerful hair dryer (70-80°C), as the glue under the lid is stronger.Do not use a knife or metal blades - they leave scratches and can puncture the battery.

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Before disassembling, take a high-resolution photo of the back of the phone, which will help the slotter to properly position the screws when assembled - their length varies!

Step 1: Removing the back cover – technique and typical errors

Start by heating the back with a hairdryer for 1-2 minutes, holding it at a distance of 10-15 cm. This will soften the glue (if any) and make it easier to separate the cover. In the Redmi 3 (2016) models, the rear panel is attached only to the latches, and in the Redmi 3 Pro/3S Prime, additionally uses perimeter adhesive.

Put a plastic mediator in the gap between the lid and the middle bezel at the headphone jack. Keep the instrument carefully along the edge, alternately snapping the locks. Don't force it -- if the lid doesn't lend itself, warm it up again with a hairdryer.

• 🔴 Mistake 1: Attempting to lid with a knife - leads to chipped plastic.
• 🔴 Mistake 2: Pressing on the center of the cover breaks the latches in the middle.
• 🔴 Error 3: Ignoring the fingerprint scanner plume (in fingerprint models) – a plume break leads to loss of function.

After removing the cover, you will see:

1. Battery with connector (fixed with glue).
2. Speaker and microphone at the bottom.
3. The fingerprint scanner plume (only in Redmi 3 Pro/3S Prime).
4. 12 screws of different lengths under a protective film.

⚠️ Warning: If the phone switches on spontaneously after removing the lid, immediately disconnect the battery.

Step 2: Battery Disconnection – Why It’s Critical

Before you unscrew the screws, be sure to turn off the battery.

1. Put a plastic mediator black battery connector (located next to the motherboard).
2. Pull it up gently - the connector should come out effortlessly.

Don't tear the battery away by force, even if it's swelling: Lithium polymer batteries can ignite if punctured or deformed. If the battery is "blown" (see from the raised back cover), contact the service center - self-replacement in this case is dangerous.

After the battery is turned off, check its voltage with a multimeter (if possible). The normal value for Redmi 3 is 3.7-4.2 V. If the indicator is below 3.5 V, the battery must be replaced.

Step 3: Dismantling the motherboard and plumes

After the battery is turned off, unscrew all 12 screws (use a magnetic screwdriver to keep them from falling out).

• 🔹 4 short – attach the fee to the frame.
• 🔹 6 medium – fix the screen module.
• 🔹 2 long - hold the camera and vibrator.

Remove the metal plate covering the plumes and gently disconnect:

1. Display plume (wide, white connector).
2. The plume of the sensory glass (thin, black).
3. The fingerprint scanner plume (only in Redmi 3 Pro/3S Prime).
4. Antenna cables (black, glued to the frame).

Remove the motherboard at an angle of 30-45°, Starting at the headphone jack. USB-port - it is soldered to the board and can come off. If the board is stuck, check if you have forgotten to disconnect the camera plume (it is often hidden under black insulation).

⚠️ Attention: In models with NFC-The Redmi 3 Pro is an extra wireless charging plume under the battery, and if it breaks, it will cause you to lose function. NFC and fast-charging.

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All the plumes in Xiaomi Redmi 3 are mounted on the latches – they need to be lifted up, not pulled to the side. If the connector does not lend itself, check if the latches are fixed with an additional screw (sometimes in 10% of cases).

Step 4: Disassemble the front panel - screen and sensor

If the purpose of disassembly is to replace the display or touch glass, act extremely carefully. In Redmi 3, the screen module is glued with a frame around the perimeter, and to separate it will require:

1. Warm up the screen with a hair dryer (temperature 60-70 ° C) for 3-5 minutes.
2. Push the glass with a suction cup at the bottom edge (near the Home button).
3. Carefully drive the plastic mediator along the edge, separating the glue.

Don't use metal tools, they scratch the glass and damage the plumes. If the screen cracks, paste it with tape so that the fragments don't fall apart when dismantled.

After taking off the screen, you will see:

• 📱 Touch glass (adhesive to display).
• 🔊 Auditory speaker (fixed to bilateral scotch).
• 📷 Front camera and sensors (soldered to the plume).

To replace only the sensor (if the display is intact), you will need a special glue B-7000 and a press for gluing, without it, the new sensor will "flake off" when pressed.

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If you have a dead zone on the sensor after you change the screen, check if the touch glass plume is properly connected, and often the problem is solved by reconnecting the connector.

Phone Assembly: How to Avoid Mistakes

Collect your phone in reverse order by following these rules:

1. Before installing the battery, clean the contacts with alcohol - oxidation can cause charging problems.
2. Twirl the screws cross-cross (like the wheels of the car) to avoid skewing the board.
3. Check the operation of all buttons before the final assembly - after installing the cover, access to them will be difficult.

For models with NFC-module (Redmi 3 Pro) make sure the wireless charging plume is not bent or sandwiched between the battery and the frame:

• 🔋 Check charging (plug the cable and make sure the current is going).
• 📶 Make sure the antennas are working (catch the network).
• 🔊 Test the speaker and microphone (record a voice note).

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

1. Is the battery connected (sometimes the connector is not fully inserted)
2. Are the contacts closed on the motherboard (look for foreign objects).
3. Is the display and sensor loops properly installed?

⚠️ Warning: If the screen flashes after assembly or artifacts appear, the display plume is probably not tightly connected.

Frequent 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 discharges quickly after replacing the battery, check:

• 🔋 Does the new battery have the capacity of the original (should be 4100 mAh).
• 🔌 Is the charging connector damaged (bend the cable - if the contact is lost, you need to replace the socket).
• 📉 Have you lost your energy saving settings (reboot your phone and reset to factory settings via Settings) → Additionally. → Recovery and discharge).

To diagnose iron problems, use the Xiaomi engineering menu:

Enter the phone app: ##4636##


Go to the Battery Information section and check the status.

FAQ: Answers to Frequent Questions