Why charging goes, and the Xiaomi phone is not charging: full analysis

The situation where a lightning icon or battery indicator appears on the screen of a Xiaomi or Redmi smartphone, but the percentage of charge remains in place or even falls, is familiar to many users. This condition is often called “false charging”, and it can be caused by both a banal software failure and serious hardware malfunctions. The power controller can receive a signal to connect the network, but not physically transfer current to the lithium polymer battery.

Users often panic, believing that the device has failed completely, but in most cases the problem is solvable at home. You need to consistently eliminate software errors, check the condition of the connectors and evaluate the quality of the accessories used. Android shell MIUI or HyperOS sometimes incorrectly processes interruptions, creating the illusion of a malfunction.

In this article, we will discuss in detail the diagnostic algorithm that will help you understand why charging is going on and the phone is not charging. We will look at the methods of software calibration, the features of the Fast Charge and the signs that indicate the need to replace hardware components in the service center.

Software failures and freeze of the power controller

The first thing to rule out is a temporary operating system failure. Xiaomi smartphones have a complex power management system that can hang around in the battery life survey cycle, in which case the device sees the cable connected, but the command to start charging does not arrive. Often, a simple reboot helps, which resets the cache of system processes.

If a simple reboot doesn't work, try a so-called "soft reboot" or reboot through an engineering menu. 10-15 So, the second it vibrates and the brand logo appears, this method forcibly initializes the charging drivers again.

• 🔋 Restart your smartphone in the usual way through the menu or by pressing the power button.
• ⚡ Perform a forced restart by holding the power button for more than 10 seconds.
• 📱 Disable all running in the background heavy applications before connecting to the network.
• 🔄 Check for system updates in the Settings section → The phone.

In some cases, the problem lies in a specific firmware update that contains bugs in the battery management module. If the problem appeared immediately after the MIUI update, it is worth considering rolling back on the previous version or waiting for a patch.

⚠️ Warning: If the phone gets too hot when it's off when you connect the charger, disconnect it immediately from the network.This may indicate a short circuit inside the board or a bloated battery.

Problems with cable, adapter and USB port

The most common physical reason why charging is going on but the phone is not charging is a damaged cable or a poor-quality power supply. The cables tend to break at the contacts, which leads to the loss of part of the conductors. As a result, the phone can determine the connection (signal contacts are working), but the bandwidth for current is not enough to charge.

And you also have to look at the USB Type-C or Micro-USB connector in your smartphone, and over time, you get pocket dust and pile stuffed in, and you get compressed and you stop the cable from coming in, and you don't close completely, and you don't activate the fast-charging protocol.

For diagnosis, use the following algorithm:

• 🔌 Try charging the device with another, obviously serviceable cable.
• 🔌 Replace the power supply (adapter) with the original or certified analogue.
• 🧹 Carefully clean the charging port with a wooden toothpick or plastic spatula.
• 🔍 Inspect the port for oxidation or black traces of smoke.

Special attention should be paid to support the protocols Quick Charge or Power Delivery. If you use a weak power supply from an old device, modern Xiaomi can consume energy faster than it comes in, especially if the screen is on, in which case it creates the appearance of charging, but the energy balance is negative.

Battery malfunctions and battery bloating

Lithium polymer batteries have a limited recharge cycle life, and over time, their capacity drops and internal resistance rises. When the resistance gets too high, the charge controller can block the current to avoid overheating or fire, although the connection indicator will burn.

The most dangerous symptom is battery bloating, and when you degrade, you can build up gases inside the battery, and the bloated battery physically presses on the screen and back, which can cause the plumes to rupture and damage to the display, and if you notice that the back cover has moved or the screen is bulging, you need to stop operating immediately.

Signs of a worn or faulty battery:

• 📉 The percentage of charge drops abruptly (for example, from 40% immediately to 15%).
• 📉 The phone turns off when 20-30% charge.
• 📉 The back cover of the body deformed or a gap appeared.
• 📉 The device is very warm in the area of the camera even in simple.

In modern Xiaomi smartphones, it is often impossible to visually assess the state of the battery without opening it, but software metrics can tell you about the problem. If the phone is older than 2-3 years, the probability of failure of the chemical element is extremely high.

Features of fast charging and protocols

Fast charging technologies like Quick Charge, Pump Express or the branded HyperCharge require coordination between the power supply and the smartphone. When connected, the phone and charger communicate, determining the maximum possible current and voltage. If this dialogue is interrupted or error-free, the system goes into safe mode with minimal current.

Sometimes the user sees the lightning icon thinking that there is an active charge, but in fact the current is only 0.5 Ampere. This is not enough to charge when the screen is on.

Comparison of charging modes:

It’s important to understand that poor-quality cables often don’t have an ID chip that tells the phone what it’s capable of, and as a result Xiaomi doesn’t risk raising voltage and charges the device extremely slowly or stops the process altogether.

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Use only original Xiaomi cables with color labeled inside the connector (usually orange or green tongue), as they are guaranteed to withstand high-power currents.

Effects of ambient temperature

Lithium batteries are extremely sensitive to temperature extremes. Xiaomi smartphones have thermal sensors built in that block charging if the battery temperature goes beyond safe limits, usually in the range of 0 to 45 degrees Celsius.

If you try to charge your phone in the winter outside or in an unheated room, the chemical reaction inside the battery slows down, the controller sees a sharp drop in voltage and stops the current supply to prevent lithium from precipitating on the anode, which irreversibly destroys the battery. Similar protection works when the phone is overheated, for example, if the phone was lying in the sun.

What to do in such situations:

• ❄️ Put the cold device in a warm room and let it warm up. 20-30 minute.
• ❄️ Do not try to charge your phone in front of a heating battery or in direct sun.
• ❄️ Remove the tight case if the device heats up during charging.

⚠️ Warning: Never put a frozen smartphone on a hot battery for quick warming.A sharp temperature drop can lead to condensation inside the case and short circuit boards.

Diagnostics through the engineering menu and resetting settings

If software methods and replacement of accessories did not help, it is worth resorting to a deeper diagnosis. In the shell of MIUI there is a hidden CIT (Customer Interface Test) engineering menu that allows you to check the condition of hardware components, including battery and charging.

To enter the menu, dial the phone app code ##6484##. In the list that opens, look for the item associated with the battery (usually called "Battery" or "Charging"). You can see the current voltage, connection status and temperature. If the status shows "Discharging" with the cable connected, the problem is hardware.

As a last resort, if you suspect a software conflict, you can perform a full factory reset. Important: before you do that, be sure to save all the important data, as it will be deleted. Go to Settings → About Phone → Settings Reset → Erase all the data.

Once reset, the phone will return to its original state, if the problem persists because of a system bug, it should disappear, and if the clean system does not see charging, the probability of hardware failure is 99%.

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If after a complete reset and check with the original cable the phone is not charged, the problem lies in the hardware: the charge controller, connector or the battery itself.

Hardware breakdowns: controller and connector

When all software and external factors are excluded, there is the option of breaking the internal components. Most often, the bottom board on which the charging connector is located fails. In low-end models of Redmi and Poco, this module is often changed entirely, which is inexpensive and efficient.

A more serious problem is the failure of the charge controller on the main board, which regulates the current supply. If it burns out (for example, due to a surge in voltage in the network or the use of cheap charging), the phone may show a connection indicator, but the battery will not pass, and it is also possible to break the plume connecting the lower board to the motherboard, especially in models with a collapsible design.

Symptoms of hardware breakdown:

• 🛠 The phone only charges at a certain position of the cable (connector problem).
• 🛠 The indicator is burning, but the percentage does not change daily.
• 🛠 The device is switched on only from charging and immediately goes out.
• 🛠 There is a smell of burning or crackling in the port area.

Repair of the charge controller requires soldering and a microscope, so it is only performed in specialized service centers. Self-repair at home without experience can lead to the final death of the device.