Xiaomi power adapters are known for their compactness, power and durability, but even they are not immune to breakdowns. If your charger stops working, warms or makes extraneous sounds, do not rush to throw it away — in 60% of cases, the problem is solved by simple cleaning, soldering or replacing capacitors. However, disassembling the power supply requires accuracy: there are high voltage elements inside, and the case is often glued or snapped in an unobvious way.
In this article, we will discuss in detail how to safely open the Xiaomi adapter (including the models on the device). 5V/2And, 18Watt, 33Wh- 67What tools you'll need, what you'll want to look for in your diagnosis, what typical malfunctions you can fix yourself, and when you should see a specialist, all the instructions are accompanied by photos of real adapters and connections.
⚠️ Warning: Disassembly of the power adapter will void the warranty Xiaomi. If the device is still warranty service, contact the service center. Also remember that working with electronics under voltage is life-threatening - all manipulations are carried out only after a complete disconnection from the network!
Preparation: security tools and measures
Before you start disassembling, make sure you have everything you need. Most Xiaomi adapters have ultrasonic welding or glue instead of screws, so a regular screwdriver will not be enough. Here is a full list of tools and materials:
- 🔧 Plastic mediator or guitar mediator - for neat separation of the body.
- 🔨 Thin flat screwdriver (preferably from the set for electronics).
- 🔥 Hair dryer construction or thermo-air station - for softening the glue (if the body is glued).
- 🧲 Magnetic mat or bowl – so as not to lose small details.
- 📸 Smartphone with camera – capture each step to properly assemble the adapter back.
- 🧤 Rubber gloves – to protect against residual stress in capacitors.
Also, prepare the workspace: it should be well lit, without carpeting (so as not to lose screws) and away from the water. 33W or 67W), Please note that there may be small ones inside. SMD-components that are easily damaged by static electricity. Use an antistatic bracelet or periodically touch grounded metal objects.
⚠️ Note: Some Xiaomi adapters (such as the Mi Charge Turbo series) have dual-insulation housing "⧠" (square in square) - this means that there is no grounding inside, and touching the board when connected to power is deadly!
Definition of type of shell: glued vs. screw
Xiaomi adapters are divided into two types according to the way the body is assembled:
- Screwing - found in older models (until 2018) and some budget charges. screws can be hidden under stickers or rubber legs.
- Glued/Welded Ultrasound – Modern Adapters (e.g. Xiaomi) 33W or Redmi 18W) They're going to be screwless. They're going to be latched and glue-free.
To determine the type of adapter you have, examine the seam between the halves of the body:
- 🔍 If you see a uniform seam without slits - the body is glued or welded.
- 🔧 If there are small holes under the screws (sometimes closed with plugs) - screw adapter.
For screw models, it is enough to twist the mounts (usually 2-4 screws under the cross screwdriver). With glued adapters, you will have to work hard: they must be carefully warmed up with a hairdryer (temperature 80-100).°C) and disconnect with a plastic mediator. Do not use metal tools, they leave scratches and can damage the board!
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If the case doesn't respond, try putting the adapter in the freezer for 10 to 15 minutes, the plastic will become more brittle, and the latches will disperse more easily, but don't overdo it, the condensation can damage the electronics!
Step-by-step: how to disassemble the Xiaomi adapter
Consider the universal disassembly algorithm on the example of the Xiaomi adapter 33W (MDY-12-ED) — This is one of the most common ones. This is a method that works for other models with minor changes.
Step 1. Disconnect the adapter from the mains and wait until it cools (if it warms up). Even when it's off, the capacitors can store charge!
Step 2: Remove the sticker (if any) that may have screws or extra latches underneath, use a hair dryer to soften the sticker glue, and gently apply the mediator.
Step 3: Warm the body with a hair dryer around the perimeter of the seam for 1-2 minutes. Keep the hair dryer at a distance of 5-10 cm so as not to melt the plastic.
Step 4: Put the mediator in the seam and gently lead along the body, alternately snapping the clamps. Start at the corner, there's usually less resistance.
Step 5: Separate the halves of the body. If you feel resistance, don't force it, you better warm up the problem area again.
⚠️ Note: Xiaomi adapters often use two-part glue, which becomes sticky when heated. If the body does not detach, put it in the freezer for 10 minutes, then try again.
Check the disconnection from the network|Take a photo of the adapter from all sides|Prepare tools and workplace|Wear rubber gloves|Check the absence of screws under the stickers-->
What's inside: the card device and typical malfunctions
And when you open the adapter, you'll see a board with components, and depending on the model, it might be:
- 🔋 Capacitors (blown or leaky - a common cause of breakdowns).
- 🔥 Throttles and transformers (can overheat when voltage surges).
- 📱 Controller chip (controls charge, often fails at short circuits).
- 🔌 USB-port or power connector (contact oxidation is a common problem).
The table below shows typical faults and their signs:
| Symptoms. | Probable cause | Can I fix it myself? |
|---|---|---|
| The adapter is not turned on, the indicator does not burn. | The capacitor failure, the chain break, the chip burned. | Yes (condenser replacement, soldering check) |
| It warms but does not charge the phone. | Faulty. USB-port | Yes (cleaning contacts, changing port) |
| Sparkling or smoke when connected | Short circuit, insulation breakdown | No (dangerous! Adapter replacement required) |
| Charges intermittently, shuts down. | Poor contact in the connector or unstable controller | Yes (contact soldering, capacitor replacement) |
Critical! If you see blackened or burned components, don't try to repair the adapter, which is a sign of a serious short circuit, and these devices are only recyclable, because it's more expensive to recover a new adapter.
How to check the adapter with a multimeter?
Xiaomi adapter repair: what can be done yourself
If you find a fault that can be fixed, follow these recommendations:
1. Replacement of capacitors
Bloated or leaky capacitors are the most common problem. They can be soldered out and replaced with similar capacitance and voltage. Use a soldering iron with a power of no more than 30 watts and a solder with flux.
2.Purge. USB-port
Oxidized or contaminated contacts lead to a poor connection. Clean them with alcohol and cotton swab. Use a wooden toothpick (not metal objects!) for mechanical cleaning.
3.Reduction check
Over time, soldering can crack, especially in places where heavy components (transformers, throttles) are attached.
4. Replacement USB-port
If the connector is shattered or the contacts are broken, you can replace it, USB Type-C female for modern adapters) and solder it, observing polarity.
⚠️ Warning: When soldering, do not overheat the board - this can damage nearby components. Use a heat sink (such as tweezers) to protect thermosensitive elements.
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If the adapter is working after repair, but warms up stronger than usual - immediately turn it off! Overheating may indicate improper soldering or a malfunction of the controller.
Adapter assembly: how to avoid errors
Getting the adapter back together is often harder than disassembling.
- 📋 Check with photos taken before disassembly. especially carefully check the location of small parts (gassing, insulators).
- 🔧 Twisting the screws cross-cross to evenly tighten the body and avoid distortions.
- 🔥 If the body has been glued, use a small amount of Moment Crystal glue or similar (not epoxy.
- 🧪 Check the operability before the final assembly: connect the adapter to the network and measure the voltage at the output.
If the body does not fit tightly, check:
- Did not get inside foreign objects (wire clippings, solder pieces).
- Are all gaskets and insulators correctly installed (they often fall out during disassembly).
- Did the latches deform during opening (they can be gently bent with tweezers).
After assembly, allow the glue (if used) to dry for 1-2 hours before connecting the adapter to the network.
When repairs are inappropriate: signs of hopeless breakdowns
Not all malfunctions of Xiaomi adapters are repairable. Here are the cases when it is better to buy a new charger:
- 🔥 Visible traces of burning on or inside the board (black spots, melted plastic).
- 💥 Bloated or burst capacitors in a high voltage circuit (near the transformer).
- 🔌 Short circuit between "+" and "-" at the output (checked by a multimeter in resistance mode).
- 📉 Unstable voltage at the output (for example, jumps between 3V and 5V).
Also consider the cost of repairs. For example, replacing the controller chip in the Xiaomi adapter 67W It can cost 70 to 80 percent of the price of a new device, and it's not cost effective to repair it.
Exception: If the adapter has sentimental value (e.g., limited batch or gift), you can restore Attempt to professionals, but remember that even after repair, such devices can work unstablely.