Modern smartphones like the Redmi Note 8 are designed to meet the needs of active users who need to manage two numbers at once, which can be splitting personal and work calls or using different pricing plans to save on the mobile Internet. Physical installation of the second SIM-cards often raise questions among beginners, especially given the miniature size of the tray and the specific design of the body.
Incorrectly installing the chip can cause the device to fail to see the network or, in the worst case, damage the contact areas. In this article, we will discuss the process of extracting the tray, determine the orientation of the map and consider the software settings necessary for the stable operation of the two carriers.
Before you start any manipulation of the smartphone body, be sure to make sure that the device is turned off. Although modern gadgets support hot replacement, to correctly identify the new operator with the Android system and to avoid voltage surges, it is better to conduct the procedure on the de-energized gadget, which ensures that the power controller correctly recognizes both modules after turning on.
Preparation of the workplace and tools
Successful installation of the second SIM card in the Xiaomi Redmi Note 8 does not require disassembly of the case or the use of complex technical tools. Everything you need is usually in a smartphone box, the main requirement is good lighting and a hard, flat surface so that small parts do not get lost and rolled away.
You will need a special key-clip (ejector) that is shaped like an elongated oval with a pointed end. If the original paperclip is lost, you can use a thin needle, but you should be extremely careful not to scratch the case or break the tool inside the hole. Do not use toothpicks, as they can split and get stuck in the mechanism.
⚠️ Warning: Never use large diameter paper clips or a stitch to extract the tray, as you risk damaging the spring mechanism or scratching the smartphone frame around the hole.
Prepare yourself. SIM-The Redmi Note 8 currently uses the Nano-SIM format, which is the smallest of the existing standards. If your card is larger and not fully cut, or if it is a combination, make sure that the active part of the chip is not damaged. Dirt or greasy spots on contacts can cause an unstable signal.
Definition of the tray type and its extraction
The Redmi Note 8 comes with a combined 2+1 or 1+1+1 slot, depending on the regional version, but it is most often a hybrid tray. It allows you to install either two Nano-SIM cards, one Nano-SIM and one microSD memory card. It is important to correctly identify the sides of the tray so as not to confuse the place for the memory card and the SIM.
The tray extraction hole is on the bottom end of the device, next to the USB Type-C connector and speaker, and it's shaped like a narrow oblong hole, insert the clip tip perpendicular to the body and press with moderate force until a characteristic click, and the tray should extend a few millimeters, after which it can be carefully removed with your fingers.
Notice the shape of the cutouts on the tray itself. One side is usually shaped like the Nano-SIM circuit, and the other side can be designed for a microSD or a second SIM. Some versions of the firmware, when removed, show a schematic image showing where to insert which chip, which is a visual cue that helps avoid errors when first installed.
💡
If the tray is not extended when pressed with a paper clip, try to slightly change the angle of inclination of the tool, but do not make excessive efforts so as not to disrupt the thread of the mechanism.
Proper orientation and installation SIM-map
The most critical thing is that the map is aligned in the tray correctly. The Nano-SIM card has a cut angle that should exactly match the shape of the notch in the plastic or metal holder. If the card doesn't lie perfectly flat, don't push it. Turn the chip over or try to rotate it 180 degrees.
The contact area (the golden stripes) should always look downwards, towards the inside of the smartphone when you insert the tray back. If you see contacts looking upwards, the map is inverted. In the Redmi Note 8 model, the tray is often two-sided, allowing you to place two cards on different sides or one card and memory.
- 📱 Take the first Nano-SIM and place it in the main slot (usually marked with the number 1), combining the cut angle with the notch.
- 📶 Set the second card in the adjacent compartment or on the back of the tray, making sure that it does not block the contacts of the first.
- 💾 If you use a memory card, it is installed on top of one of the SIM cards or in a separate compartment, depending on the design of the particular tray.
Important: Make sure that the card lies strictly within the allotted space and does not protrude beyond the edges of the tray, otherwise, when closing the case, mechanical damage to the chip is possible.
☑️ Pre-insertion check
Comparison of tray configurations in different versions
Xiaomi often releases different modifications to its devices for different markets. The tray configuration in the Redmi Note 8 may vary depending on whether the phone is purchased in China, Europe or Russia. Understanding the differences will help avoid confusion if you purchased a device imported through parallel imports.
In the global version, the most common full-fledged triple slot, where the two SIMs and memory card do not conflict with each other. In the Chinese versions, the second slot is often hybrid, meaning you have to choose between a second SIM card and a memory extension. Below is a table that helps identify your option.
| Type of tray | Slot 1 | Slot 2 | Slot 3/Hybrid |
|---|---|---|---|
| Global version | Nano-SIM | Nano-SIM | microSD (separately) |
| Chinese version | Nano-SIM | Nano-SIM / microSD | No (hybrid) |
| Single SIM | Nano-SIM | microSD | No. |
If you find that the memory card doesn't physically fit with the second SIM, you've got the hybrid slot version, and you've got to choose between two active links or one line and a large storage for photos and videos, and you can't software-bypass this limitation because it's a feature of the hardware platform.
Tray insertion and primary start
Once the cards are placed in their cells, you need to carefully insert the tray back into the case of the smartphone. Notice the shape of the tray: it has a bevel on only one side, which prevents the wrong insertion. You do not need to use force; if the tray does not enter, turn it over.
Push the tray to the end until it's equal to the frame. The characteristic click may be missing, but you'll feel the mechanism locked. You can now turn the device on by holding the side Power button. The boot process can take a little longer than usual, as the system interrogates both communication modules.
⚠️ If the smartphone is turned on, it says “No” SIM-"Master" or "Put in" SIM", Turn off the device and check the density of the cards.
When you first start up, MIUI automatically detects two active cards, and you'll see notifications on the screen asking you to set your preferences for each card, and SIM 1, which is usually the default for calling, and you can choose between two available networks for mobile Internet.
Setting up two SIM-map MIUI
After the operating system is successfully launched, you need to set your card priorities correctly. To do this, go to Settings, then select the item SIM-Maps and mobile networks. This shows both maps with their names and operators.
In this menu, you can assign which card will be used by default for voice calls and which card will be used for data transfer. PIN-code that adds an extra layer of security to your data, so if one of the cards is rarely used, you can temporarily disable it software without physically removing it.
- 📞 For calls: select Always Ask if you want to select a number before each call, or assign a primary card.
- 🌐 For the internet: it is recommended to use a card with unlimited traffic or the best coverage in your area.
- 💬 For SMS: You can assign a separate card to send messages, which is convenient for registering in the services.
What if 4G doesn’t work on the second SIM?
Possible problems and ways to solve them
Even if installed correctly, there may be situations where the second SIM card is not identified or is not functioning stable, often the problem lies in oxidized contacts on the card itself or in contamination of the tray, wipe the SIM contacts with a soft dry cloth or eraser, trying not to damage the gold spray.
Another common reason is that the card is incompatible with the operator's networks, if the card is very old and does not support the card. 4G/LTE, In modern networks, it may not work correctly, in which case you need to contact the operator's salon for a free replacement with a new Nano-SIM with support for modern standards.
⚠️ Note: Do not use homemade adapters from Micro-SIM to Nano-SIM. They are often thicker and can get stuck inside a smartphone, which will require expensive repairs at a service center.
If the software card is visible but the network is not catching, try resetting the network settings. Go to Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. This action will return network settings to factory values and often solves network logging problems.
💡
If none of the SIM cards is detected after resetting and reinstalling, the communication module itself or the antenna plume is likely to be faulty, which requires diagnosis in the service.