Xiaomi Mi 4 Pro (released in 2015) is still popular with enthusiasts due to its iron body, powerful filling and upgrade capabilities, but disassembling this device is not an easy task: there is no removable back cover, and the body is fastened with glue and latches. In this article, we will discuss how to properly disassemble the Mi 4 Pro without damaging the plumes and losing small parts.
Before you start, consider this smartphone has a unique design with an aluminum body and glass inserts, which requires a special approach when disassembling. Mistakes can lead to damage to antenna lines, tearing off the plume of the touchscreen or even cracks in the case. If you have never dismantled smartphones, you better consult a specialist.
Preparation for disassembly: tools and security measures
To disassemble the Xiaomi Mi 4 Pro, you will need:
- 🔧 Plastic mediators (2-3 (a) for the purpose of carefully sliding the.
- 🔨 Thin screwdriver T3 and T5 — screw-in.
- 🔥 Hair dryer or thermo-air station - for softening the glue.
- 🧲 Magnetic mat or tray - so as not to lose screws.
- 📱 Suction - to raise the screen (optional).
Important: Don't use metal tools to tamper with the body - they leave scratches on the aluminum. SIM-If the battery is swelling, disassembly becomes extremely dangerous (risk of fire.
⚠️ Warning: If your Mi 4 Pro was in water or dropped, it could have corrosion or microcracks on the board.
Step 1: Removing the back cover is the most difficult step
The body of the Mi 4 Pro is glued around the perimeter, so you can't just take it off. You'll have to heat it with a dryer (temperature ~60-70°C) for 2-3 minutes, evenly leading around the edges. Don't overheat - plastic clips inside can deform!
After heating:
- Insert a plastic mediator into the gap between the case and the screen (start with the lower right corner where there are no plumes).
- Carefully drive the mediator along the body, without going deeper than 2 mm - antenna lines pass inside.
- As soon as the lid begins to succumb, remove it with your fingers (it can "shot" due to spring contacts).
Under the lid, you'll see:
- 🔋 Battery (stick-on).
- 📡 Antenna modules (do not touch them unnecessarily!).
- 🔩 12 screws of different sizes (remember where you stood!).
No damage to the plumes | Integrity of antenna contacts | No corrosion traces on the board | All screws in place (12 pieces)
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Step 2: Shutting down the battery – why it’s critical
Before you continue, be sure to disconnect the battery.
- Unscrew 2 screws next to the battery connector (they can be under a black protective film).
- Put a plastic scapula (not metal!) on the battery connector.
- Make sure the contacts are not closed – touching the board can cause a short circuit.
If the battery is swelling, don't try to remove it yourself - it can burst or catch fire.
- 🚫 Don't puncture the battery.
- 🔌 Don't plug the charging in.
- 📞 Contact the service with the function of recycling Li-ion batteries.
⚠️ Warning: The Mi 4 Pro has capacitors that can keep it charged even after the battery is turned off. Don't touch the board with your bare hands - use an antistatic bracelet or at least rubber gloves.
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If the screws don't unscrew, moisten them with WD-40 or alcohol and wait 5 minutes. Don't apply force - the thwarted thread will complicate the assembly.
Step 3: Removing the motherboard – working with plumes
The board in the Mi 4 Pro is mounted on 8 screws and connected to the screen with three plumes: display, touch screen and additional (for sensors).
- Unscrew all the screws (they are of different lengths - remember the location!).
- Take care of the stains and put them on the side (not up!).
- Raise the charge over the edge, don't pull the connectors.
Common mistakes at this stage:
| Mistake. | Effects of consequences | How to avoid |
|---|---|---|
| Sharp pulling of the plume | Contact break, dead screen | Just throw it on the side, not up. |
| Loss of screws | Incorrect assembly, KZ | Use a magnetic mat |
| Touching boards without grounding | Static electricity kills chips | Working in antistatic gloves |
If you only need to replace the battery or the speaker, you don't have to retrieve the board, but you have to remove the charger plug or the microphone to repair it.
What to do if the plume is broken?
Step 4: Disassemble the screen when necessary
The Mi 4 Pro has three layers: glass, touchscreen and a matrix, and if you only have a glass crack, you can try replacing it separately, but that requires special equipment (laminator).
For screenshots:
- Heat the display edge with a hairdryer (temperature ~50°C).
- Tap the glass with a plastic blade, starting at the bottom edge.
- Carefully separate it from the body, watching the plumes.
Important: There are two loops on the screen, one on the bottom, one on the left. Don't pull the screen up until you've disconnected them!
⚠️ Attention: If the screen doesn't separate, don't force it -- you probably haven't warmed up enough. Reheat and try again. Broken glass can cut the plumes!
Step 5: Replacing the battery – nuances for the Mi 4 Pro
The battery in this smartphone is glued to double-sided tape, and it needs to be replaced with caution.
- Disconnect the battery connector (as described above).
- Put a plastic blade on the battery from any end.
- If it doesn’t give in, put a thin guitar string or plastic card under it and “saw” the glue, gradually shifting the battery.
For the new battery, use the original adhesive (e.g. 3M 9448A) or double-sided 0.5mm thick tape. Do not drag the screws when assembled - this can deform the case.
Tips for choosing a battery:
- 🔋 Original article: MB38 (3,080mAh).
- 🔄 Analogues: Patona or Kwxm (but check reviews!).
- ⚡ After replacement, perform 3 full charge/discharge cycles for calibration.
(1) Whether the connector is properly connected.
(2) Whether there is a latch of the plume under the battery.
3) Condition of contact on board (possible corrosion).-->
Step 6: Building – How to Avoid Mistakes
The assembly should take place in reverse order, but there are several critical points:
- 🔩 Screws: use a diagram of their location (you can take a photo before disassembling).
- 📶 Antennas: Make sure the contacts are not bent and fit tightly to the board.
- 🔋 Battery: Before connecting, check the voltage with a multimeter (should be) ~3.7-4.2V).
After assembly:
- Don’t turn on your smartphone right away – wait 5-10 minutes (capacitors can be charged).
- Check the operation of all sensors (Engineering Menu hardware test: ##4636###).
- If the screen does not respond to touch, check the connection of the touchscreen plume.
If you've had artifacts on your screen or sensor problems after you've assembled, chances are you haven't pressed the plumes tight enough. Take your smartphone apart again and check for them to fix.
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:
| Problem. | Possible cause | Decision |
|---|---|---|
| Not included. | The battery or board plume has disconnected | Disassemble, check all the connectors |
| No network. | The antenna or its contacts are damaged. | Check the integrity of antenna lines |
| The screen flashes. | Poor contact of the display plume | Reconnect the plume, clean the contacts with alcohol |
| Touchscreen's not working. | The plume or its connector is damaged. | Replace the plume or clear the contacts |
If after disassembly the smartphone overheats or discharges quickly, there are two possible reasons:
- The board was damaged by static electricity.
- The thermopast on the processor is dry (replacement required).
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If you have any extraneous sounds (squeaking, crunch) after assembly, you may have misplaced the speaker or vibration motor, and take your smartphone apart and check their position.