Installing a communication module in a smartphone is perhaps the most basic but critical operation that every new device owner faces.The Xiaomi Redmi 7 model, released in 2019, features a hybrid slot, which requires the user to be careful when choosing a configuration: use two SIM cards or one SIM card and a memory card. Installation incorrectly can lead to the device not seeing the network or not reading the drive, so it is important to follow the algorithm of actions clearly.
In this article, we will discuss in detail the process of tray extraction, the orientation of the chip and the software configuration of the network after physical installation. Many users make mistakes by trying to insert the tray on the wrong side or making excessive efforts, which can damage the mechanism. Careful study of the instructions will help you avoid mechanical damage and quickly activate communication.
The process of preparing your smartphone for work takes only a few minutes, but requires care. We will consider not only the mechanical part of the process, but also the nuances of software configuration, which are often ignored. Proper switching of equipment is the key to stable signal reception and long service of the contact group of your Redmi 7.
Tool preparation and tray inspection
Before you start installing, make sure you have everything you need on hand.The Xiaomi Redmi 7 usually comes with a special paperclip to extract the tray, however, it is often lost or missing if the phone is bought with hand.
The tray itself is specifically designed, it's on the top end of the device, and it's hybrid, which means that the second place is either for the second Nano-SIM SIM card or for the microSD card. The physical structure of the tray doesn't allow two SIM cards and flash memory to be used at the same time, so prioritize.
⚠️ Warning: Before any tray manipulation is initiated, it is strongly recommended to turn off the smartphone.While current standards allow hot replacement, power cuts minimize the risk of short circuits and equipment failure by the system.
Look at the tray in good light, and you'll notice that it has a bevelled angle on one side that matches the shape of the chip, and you can have pictograms on the tray surface that indicate the correct orientation, but you don't have to rely on them alone, you can visually check the position of the contacts.
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Use a soft microfiber fabric to wipe the tray from dust before installation. Small villi can prevent the contacts from fitting tightly.
The process of removing the SIM card tray
To begin with, find the tray extraction hole on the top end of the Xiaomi Redmi 7 body. It is located next to the 3.5 mm headphone jack. Place the tool (clip or needle) perpendilarly into the hole. You don't need to enter the tool too deeply - just feel the light emphasis of the mechanism.
And you can apply a small but steady force, pressing just down the axis of the hole. You should hear a quiet click, and the tray will move out a few millimeters. The spring mechanism in this model is quite tight, so if the tray doesn't come out, check the angle of the tool -- it should be perfectly straight.
Carefully pull the tray with your fingers over the protruding edge. Don't pull sharply so as not to damage the contacts inside the smartphone. If the tray is stuck, try swaying it from side to side with minimal amplitude, while gently pressing inwards, and then try to retrieve it again.
Proper installation of SIM card and memory card
The most important step is to get the chip right. Redmi 7 uses the Nano-SIM format, which is the smallest of the existing standards. Make sure your SIM card is broken along the right contour and doesn't have plastic burrs that can get stuck in the slot.
Put the SIM card in the appropriate recess of the tray. The golden contacts should look downwards to the inside of the tray. The bevelled corner of the card should match the bevelled angle of the notch in the tray. If the card doesn't fall flat, don't press it, flip it over and try again.
If you plan to use a microSD card, it is installed in the second slot. It is also important to observe orientation: the contacts of the memory card also need to look down. Unlike some other models, in Xiaomi, the tray often has latchers on the edges that hold the card.
☑️ Pre-installing check
After you've laid the cards, check if any of them are protruding over the edge of the tray. The height of the setup is critical: if the map is above the level of the sides, you risk damaging the contacts when you push the tray back into the phone.
What to do if the SIM card is larger than the Nano format?
Inserting the tray back into the smartphone
Once you've successfully laid the cards, you need to put the tray back in place. Take the smartphone so that the top end is directed towards you, and the screen is looking down or up -- whichever way you like, the main thing is to see the hole. The tray has only one right side to insert.
Take a close look at the tray profile. On one side, it can be a little thicker or have a step. In Redmi 7, the tray is usually symmetrical in thickness, but has bevels. If you feel resistance when you enter, don't press. Take out the tray, flip it 180 degrees and try again.
Push the tray smoothly, without jerking. It should enter before the characteristic click or match the body of the phone. The tightness of the case depends on the density of the tray, although the Redmi 7 model does not have full moisture protection, the dense fit prevents dust from entering.
| Position in the tray | Type of card | Orientation of contacts | Note |
|---|---|---|---|
| Slot 1 (External) | Nano-SIM | Down. | The basic SIM card. |
| Slot 2 (Internal) | Nano-SIM | Down. | Unless you are using a microSD |
| Slot 2 (Internal) | microSD | Down. | To expand memory |
| Both slots | - | - | You can’t use 2 SIM + SD at the same time. |
Network settings after installation
Once the smartphone is turned on, the system will automatically detect the SIM card installed. The signal level and operator name should appear on the screen. If this does not happen, go to the Settings menu. → SIM-maps and mobile networks. Here you'll see the status of each card.
In this section, you can assign a default SIM card for voice calls and for mobile Internet. For Xiaomi Redmi 7 with its 1520×720 screen, the settings interface can take up several pages, so scrolle through the menu carefully.
⚠️ Warning: If the phone says "No service" or "Emergency calls only," check if the SIM card is inserted correctly. Often the problem lies in the oxidation of contacts or the loose fit of the tray.
You can also set up your preferred network type in this menu. For maximum speeds, choose Preferably 4G (LTE). If 4G coverage is unstable in your region, the system will automatically switch to 3G or 2G, ensuring continuity of communication.
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Properly setting network priorities in the smartphone menu saves battery power by preventing constant signal search where there is none.
Addressing common problems
Sometimes users are faced with a situation where the phone does not see the SIM card even after installing it correctly. First of all, try to restart the device. Software failure of the radio module service is a frequent occurrence in the MIUI shell, and restarting often solves the problem.
If the reboot didn't work, remove the tray and wipe the SIM card contacts with a soft eraser or dry cloth. Fat spots or oxidation can prevent signal transmission. Also check if the tray itself is deformed - in cheap phone models, metal sometimes bends.
In rare cases, the problem may be with the SIM card itself. Try installing it on another phone. If it doesn't work there, contact the carrier's salon to replace it. Older SIM cards may not support the modern encryption protocols used in 4G networks.
Make sure your version of MIUI is updated to the latest available for Redmi 7. Updates often contain patches to improve compatibility with network operators.