Many smartphone owners Samsung face a paradoxical situation: despite the widespread development of fourth generation networks, the standard 3G sometimes turns out to be much more stable. In conditions of poor reception or overloaded provider towers, the device may constantly lose the LTE signal, which is why the Internet actually disappears and the battery charge rapidly dwindles. A forced transition to an older, but reliable communication protocol is often the only solution to the problem.
Let's take a closer look at how to change the network settings on your device. This process may be required not only to stabilize the connection, but also to save energy in areas of poor coverage, where the communication module is working at the limit of its capabilities, trying to hold the signal 4G.
In this article, we will analyze both standard methods through the settings menu, and hidden engineering codes that allow you to access advanced parameters of the radio module. You will find out why the phone may not allow you to select the desired mode and how to bypass these restrictions safely.
Reasons for forced switching to 3G
Before changing the network configuration, it is worth understanding why this is necessary at all. Modern smartphones are configured to automatically select the best available connection, but the algorithms do not always work correctly in real-world conditions. Often the phone clings to a weak signal LTE, instead of switching to a stable one H+ or 3G.
The main problem lies in the physics of radio wave propagation. The 4G signal has a higher frequency and penetrates walls and ceilings less well. If you are in a basement, a thick-walled building or in a remote rural area, the communication module will constantly jump between modes, causing disconnections.
- 📶 Stability: In areas of poor reception, 3G provides a continuous connection without constant reconnections.
- 🔋 Battery saving: Searching for a 4G network with a weak signal makes The processor and radio module operate at increased power, which quickly drains the battery.
- 📞 Call quality: Some operators still use 3G technologies for voice calls (CSFB), and fixing to this standard can improve speech intelligibility.
⚠️ Attention: Forcing 3G on will significantly reduce the maximum data download speed. This mode is not suitable for watching videos in 4K or downloading large files.
Standard method through the settings menu
The safest and easiest method of changing the network type is available to every user without the need to obtain root access or use third-party software. The interface One UI from Samsung is intuitive, but the location of the items may vary slightly depending on the firmware version.
First, open the main menu of your device and find the icon Settings. In the list that opens, you need to scroll down to the section Connections. This is where all the parameters responsible for the operation of wireless modules are concentrated, including Wi-Fi, Bluetooth and mobile communications.
Inside the section Connections select item Mobile networks. The system may ask you to confirm the action if you use two SIM cards - in this case, indicate the card for which you want to change the network priority. Next, find the line Network mode.
If the "Network mode" item is inactive (gray), make sure mobile data is turned on, or try temporarily removing and inserting the SIM card back.
In the list that opens you will see several options. The standard choice is usually at 5G/4G/3G/2G (auto-connection). You need to select the option that explicitly indicates only 3G or WCDMA. In some software versions, this may look like Only 3G or 3G/2G (auto-connection).
☑️ Checking network settings
Using the engineering menu to select a network
If the standard menu does not provide the desired option or the selection is not saved, you can use the hidden service menu. This method gives access to deep radio module settings that are usually hidden from the average user. Be extremely careful when changing the parameters in this section.
Open the application Phone (dialer) and enter the special code: ##4636##. Immediately after entering the last asterisk, the service menu Testingshould open on the screen. If the code did not work on your model, try an alternative option for Samsung: #0011# (service mode) or #2263# (frequency band selection).
In the menu Phone information find the drop-down list with the name Set up preferred network type. There is a much wider range of options available here, including specific combinations of standards. To force 3G on, select WCDMA only.
⚠️ Attention: Do not change other parameters in the engineering menu, especially those related to frequencies (Band), if you do not know exactly which bands your operator supports in your region. This may lead to a complete loss of communication.
After selecting a mode, the screen may go dark for a second or a notification about rebooting the radio module will appear. This is a normal system reaction to a change in communication protocol. Check the icon in the status bar - instead of 4G or LTE the icon should appear 3G or H+.
What to do if the code does not work?
On some new Samsung models with the latest versions of Android, access to menu 4636 may be blocked by the manufacturer. In this case, try installing the "Force LTE Only" application from the Play Store, which creates a shortcut to this menu.
Features of working with dual SIM cards
Owners of devices that support Dual SIM should take into account that network settings are applied individually for each slot. However, the architecture of some smartphones is such that when 4G is activated on one card, the second is automatically switched to 2G/3G mode only for receiving calls.
If you want to switch both cards to 3G mode, you will have to alternately select the active SIM card in the settings and change the network priority for it. Go to Settings → Connections → SIM card manager.
Here you can assign which card is used for mobile data and which for calls. It is important to understand that high-speed Internet (4G/5G) usually only works on one selected card. In this case, the second card will function in a simplified mode.
| Parameter | SIM 1 (Data) | SIM 2 (Calls) | Both cards 3G |
|---|---|---|---|
| Internet speed | High (4G/5G) | Low (2G/3G) | Medium (3G) |
| Call stability | Depends on VoLTE | High (CS) | High (CS) |
| Battery consumption | Medium/High | Low | Low/Average |
| Recommendation | City, good connection | Dacha, reception area | Weak signal areas |
Influence of telecom operator and coverage area
Switching success directly depends on the policy of your mobile operator. Some providers are actively shutting down 3G towers, redirecting all traffic to 4G and 5G. In such cases, forcing the selection of 3G may result in a complete lack of network (“No service”).
Before changing settings, it makes sense to check your operator's coverage map. If your area has already been upgraded and 3G is disabled, no amount of phone settings will make it work. In this case, the solution is to use 4G or change the operator.
It is also worth considering that the rules change when roaming. Abroad, your phone may automatically register with partner networks where 3G support may be limited or charged differently. Always check the roaming conditions before traveling.
If after switching to the mode Only 3G the phone says "No network", try rebooting the device. Sometimes the radio module requires a complete reboot to correctly register with the network of the selected standard.
Returning to automatic mode and solving problems
If you realized that 3G does not solve your problem, or you have returned to the zone of reliable 4G reception, you need to return the settings back. Otherwise, you will artificially limit the speed of your smartphone.
Return to the menu Network mode and select the very first item in the list, usually called 5G/4G/3G/2G (auto-connect). This will allow the phone to independently select the best available communication standard at the current time.
In rare cases, after changing the mode, the network may not appear immediately. Try turning it on and off Flight mode. This action will forcibly re-register the device in the operator's network and update information about available towers.
⚠️ Attention: Settings interfaces can be updated by the manufacturer. If you do not find the described items, check the official instructions for your specific model on the Samsung website, as the menu layout may change with the release of new versions of One UI.
Returning to automatic mode (5G/4G/3G/2G) is a mandatory step after leaving a poor coverage area to restore high speed Internet.
Frequently asked questions (FAQ)
Why did the Internet become very slow after switching to 3G?
This is expected behavior. 3G technology (UMTS/HSPA) has a physical bandwidth limitation that is significantly lower than 4G (LTE). The speed can drop to 2-10 Mbit/s, which is enough for instant messengers, but not enough for heavy content.
Does 3G mode affect the quality of voice calls?
In most cases, the quality of calls in 3G is even better than in 4G without VoLTE support, since a dedicated voice channel is used. However, if the operator uses VoWiFi technology or advanced VoLTE, switching to 3G may disable these features.
Is it possible to enable 3G for only one SIM card on a dual-SIM phone?
Yes, it is possible. You need to go to the mobile network settings, select a specific SIM card (for example, SIM 1) and change the network mode only for it. The second card will remain in automatic mode or the one that was installed previously.
Will the phone heat up less in 3G mode?
As a rule, yes. In areas with a weak signal, the 4G modem operates at maximum transmitter power in an attempt to maintain the connection, which causes heating. A stable 3G signal requires less energy to maintain communication, reducing heat dissipation.
What does H+ mean instead of 3G?
H+ (HSPA+) is an improved version of the 3G standard. It provides higher data transfer speeds, close to entry-level 4G. If you see H+, it means the phone is operating in 3G mode, but at the highest possible speed for this standard.