The situation when only one module stops charging from a pair of wireless headphones is one of the most common complaints of Xiaomi equipment owners and sub-brands like Redmi or Poco. The user notices that the indicator on the case does not light up when you put the device inside, or one earphone discharges much faster than another, demonstrating the abnormal behavior of the power consumption system. Often the problem lies not in the physical breakdown of the battery, but in the banal violation of contact or software failure of the power controller.
In this article, we will take a closer look at the mechanical and software causes of malfunction so you can make your own diagnosis. Contact oxidation and sensor sticking are 80 percent of all cases that are easily eliminated at home without going to a service center. However, it is important to understand that lithium polymer batteries are sensitive to operating conditions, and deep discharge can become critical.
Take your time to throw away the gadget or carry it for repair right away. Often, a simple cleaning or proper reset procedure is enough to bring Mi True Wireless Earbuds back to life. We'll look at the simple to complex algorithm of actions, including checking the voltage in the case and forcing the activation of the "sleeping" battery.
Mechanical causes of lack of charge
The most obvious but often overlooked cause is physical pollution: In the process of operating on the headphone contact pads and inside the charge case, earwax, skin fat and dust accumulate, these substances form a dielectric film that blocks the transmission of current. Contact pins in the depths of the case landing site can be infused or oxidized, especially if the device was operated in high humidity.
Now, if you look at the magnets, if the magnet in one of the headphones is weakened or shifted because of a fall, the device may not be fully immersed in the groove of the case, and visually, it's hard to see, but even half a millimeter of gap breaks the electrical circuit, and see if the earphone sticks tightly to the bottom of the charging station.
⚠️ Note: Do not use metal objects (needles, pins) to clean the contacts inside the case. You may accidentally close the circuit or damage the insulation, which will short-circuit and the motherboard will fail.
It's also worth considering the state of the case's charging port itself, and if you charge your device via USB-C or Micro-USB, the connector might squirm, so the cable might not be fully inserted, and only enough power to charge one of the more priority headphones for the controller, or the current doesn't come in at all.
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Use a dry toothbrush with soft bristles to clean the contacts carefully. To degrease, you can slightly moisten the brush with isopropyl alcohol, but do not pour the liquid inside the device!
The problem of deep battery discharge
The lithium-ion and lithium-polymer batteries used in Xiaomi Earbuds have a critical voltage threshold. If the headphone was discharged for several months, the voltage on its cell could fall below the minimum value necessary to start the charge controller, in which state the device “does not see” charging and does not respond to installation in the case.
The power controller blocks charging for safety reasons to prevent the battery from overheating or bloating, but often this unit can be removed by push-off charging, placing the headphones in a case and connecting it to a power source with a current of at least 1 Amp.
The process of "resuscitation" can take a long time. Leave the case with headphones on charge for at least 2-3 hours, even if the indicators do not burn. Low currents can slowly "swing" the chemical process inside the battery. If the indication does not appear after 3-4 hours, the probability of failure of the battery is high.
- 🔋 Leave the case with headphones on charge for the whole night (8)+ hours).
- 🔌 Use a cable and power supply, in the serviceability of which you are sure to 100%.
- 🌡️ Avoid charging in the cold or in direct sunlight.
- 🔄 Periodically remove and insert headphones into the case while charging.
Program failure and need for resetting
Sometimes the hardware is fine, but the headphone software freezes. The internal firmware of the Bluetooth chip may not properly process the charge status signals, sending false data to the smartphone or ignoring the case commands, in which case a forced reboot or a complete reset to factory settings is required.
Most Xiaomi models (e.g. AirDots, Redmi Buds) use a feature button on the case or touch zones of the headphones themselves to reset, and the standard procedure is to hold the reset button on the back of the case for 15-20 seconds until the indicator flashes white or orange.
The algorithm for a complete reset (Hard Reset):
1. Remove the device from the Bluetooth list on your smartphone (“Forget the device”).
2. Place both earphones in the case.
3. Leave the case lid open.
4. Press and hold the reset button for 20-30 seconds.
5. Wait for 3-5 quick flashes of the indicator.
6. Close the case and open again to pair.If the button is missing, the reset is often done by touching the touch zones of both headphones simultaneously, removing them from the case, turning them off (clutching the sensor for 5 seconds) and then turning them back on, holding the sensors down for 20-30 seconds before the reset indication appears. The exact combination depends on the specific earbuds model.
☑️ Checklist for resetting settings
Diagnostics of the charging case
Now, the problem is that the charger case is a complex electronic device with its own battery and power distribution board, and if the distribution board fails on one channel, the second headphone will charge and the first one will not.
You can check this by eliminating it. Try changing the headphones in the case. If the problem moved with the headphone (that is, it does not charge again in the new socket), then the headphone itself is to blame. If another headphone stopped charging in the same socket where the first one was previously lying, then the seat of the case is malfunctioning.
| Symptoms. | Probable cause | Decision |
|---|---|---|
| Case indicator doesn't light up | Battery of the case or port breakdown is discharged | Replace the cable/power supply |
| It only burns when you move. | Oxidation of contacts or backlash | Cleaning contacts with alcohol |
| The headphone charges, but quickly sits down | Battery degradation (wear and tear) | Battery replacement |
| The indicator flashes red. | Charging error or short circuit | Moisture testing |
Also, pay attention to the behavior of the LED indicator on the case itself. In some Xiaomi models, the color of the indicator signals the state of charge of the particular earpiece that was last removed, or shows the status of the left / right channel.
Why does the case discharge faster than headphones?
Effects of moisture and operating conditions
Most modern Xiaomi headphones have IPX4 or IPX5 moisture protection. This means splash and sweat resistance, but not water or steam protection. Moisture entering the case is a common cause of charging failure. Water caught on the contacts causes corrosion, and evaporates leaves a salt plaque that conducts current chaoticly.
If the earphone is in the rain or you forget it in the bathroom, do not try to immediately put it on charge. This is guaranteed to lead to electrolysis and combustion of the controller. You need to completely dry the device. It is best to use silica gel bags, placing the headphones and case (separately) in a sealed container with a moisture absorber for 24-48 hours.
⚠️ Warning: Don't use a hair dryer to dry headphones! hot air can melt the speakers' adhesive joints and damage the lithium battery, making the device dangerous to use.
In addition to moisture, temperature is critical. In the cold below -10°C, the capacity drops dramatically and the chemical reaction inside the battery temporarily fails. If you bring the headphones in the cold, let them warm to room temperature when turned off for 30-60 minutes before trying to charge.
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Moisture and extreme temperatures are the main enemies of electronics. Compliance with the temperature regime of operation prolongs the life of batteries by 2 times.
When professional repairs are needed
If all of the above methods — cleaning, resetting, long-term charging and drying — have not helped, most likely the problem is hardware in nature, it can be the physical death of the battery cell, the departure of the plume inside the earphone or the combustion of the charge controller on the board.
Replacement of the battery in a TWS-It's very difficult for headphones to have a monolithic body design, and to get to the battery, you often have to open the body, which requires heating and special tools, and there's a high risk of damaging the fragile membranes of the speakers or breaking the thinnest wires.
In the event of a hardware breakdown, the most rational solution would be to go to an authorized service center or replace the device if the warranty is still in place. Repairing one earphone can cost up to 70% of the cost of a new set, making the procedure economically inefficient.
- 🛠️ The battery is swelling and bulging out of the body.
- 🔌 Contacts inside the case are broken or missing.
- 💧 The headphone was completely submerged in water.
- 🔥 The device is very hot during charging.