Why Wi-Fi works on one phone, but not on another: A full breakdown of the problem

On one phone Wi-Fi connects, but there is no internet — a typical problem where the router correctly distributes the network to other devices (a laptop, tablet, or second smartphone), but the first device displays the error "No internet access" or a yellow triangle with an exclamation point. The cause can be found in the phone's settings (for example, an incorrect IP or DNS), router limitations (MAC filtering, invalid frequency range), or issues with the ISP. However, local connection settings are most often to blame.

In this article we will look at all possible reasons, where Wi-Fi internet may be unavailable on one device, while everything works on others. From trivial configuration errors to hidden protocol conflicts, you'll get clear diagnostic algorithm and solutions for Android, iPhone and all router models. No unnecessary theory—only practical steps with explanations.

Important: If the problem appeared after updating the phone firmware or changing the router, In 80% of cases, IP protocol settings or Wi-Fi frequency conflicts are to blame.. More on this in the relevant sections below.

1. Checking the basic parameters: what to do first

Before delving deeper into the settings, rule out obvious causes. Start with these steps:

• 🔄 Restart both devices — your phone and router. Turn them off for 30 seconds, then turn them on again. This will clear temporary network protocol errors.
• 📶 Check the coverage areaIt's possible the second phone is in a "dead zone," where the signal is present but not strong enough for a stable internet connection. Move closer to the router.
• 🔗 Make sure the problem isn't with your ISP.Open the website on your work phone. 2ip.ru or speedtest.net — If there is no internet there either, the problem is with the connection, not your device.

If the problem persists after rebooting, proceed to the next step. Please note: if the "non-working" phone shows the message "Wi-Fi" in the Wi-Fi settings Connected, without internet, this indicates problem with DHCP or DNS — more about this in the section on IP configuration.

2. IP Address Conflict: Why Your Phone Can't Access the Network

One of the most common reasons is Incorrect IP address assignment router. This happens when:

• 🔢 A static IP address is manually entered on the phone, which conflicts with the router's DHCP pool.
• 🔄 The router “forgot” the previously assigned address and does not update it (typical for cheap models).
• 🛡️ The MAC address filter is enabled in the router settings, but your phone is not listed there.

How to check and fix:

1. On a non-working phone, go to Settings → Wi-Fi → [Your network] → Network settings (or "Network management").
2. View the parameter IP address:
   • If the address indicated there is something like 169.254.x.x - This emergency APIPA, meaning that the phone was unable to obtain an IP from the router.
   • If the address starts with 192.168. or 10.0., but the Internet doesn't work - try manually entering DNS (for example, 8.8.8.8 And 8.8.4.4 from Google).

Check your phone's current IP address|

Compare it with the router's DHCP pool (192.168.1.100–192.168.1.200)|

Try manually entering DNS|

Reset your phone's network settings

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If the problem persists after the reset, go to the router control panel (192.168.1.1 or 192.168.0.1) and check:

• Is it included? DHCP server (usually in the section LAN or Local area network).
• Is your phone number not on the list? blocked devices (chapter MAC filter or Access control).

3. Wi-Fi Protocol Issues: 5 GHz vs. 2.4 GHz

Many modern routers operate in two ranges - 2.4 GHz And 5 GHzIf one phone connects to 2.4 GHz, and the other one - to 5 GHz, the difference in speed and stability can be dramatic. Here's why:

How does this affect your problem:

• 📱 If old phone (For example, Samsung Galaxy S5 or iPhone 5) doesn't see the network 5 GHz, it automatically connects to 2.4 GHz, where there may be a lot of interference.
• 🔄 If the router is configured to separation of networks (For example, MyWiFi_2G And MyWiFi_5G), one phone may be clinging to a congested channel, and the other to a free one.

Solutions:

1. In the router settings (192.168.1.1) find the section Wi-Fi or Wireless network and check:
   • Are both ranges included (2.4 GHz And 5 GHz).
   • Isn't there a tick? Split the networks (if yes, remove it so that the router itself selects the optimal range).

Settings → Wi-Fi → [Your network] → Band → 2.4 GHz

4. Security settings: why the phone fails authentication

If your phone connects to Wi-Fi but disconnects after a few seconds or shows “Authenticating…”, the problem is network security settingsHere are the most common scenarios:

• 🔒 Incompatible encryption typeFor example, a router uses WPA3, and the old phone only supports WPA2.
• 🔑 Incorrect password (yes, even if you're sure you entered it correctly.) Sometimes case symbols or spaces get swallowed up when you type.
• 🛡️ MAC address filteringThe router may block connections from devices whose MAC addresses are not whitelisted.

How to fix:

1. Check the security type in your router settings:

   192.168.1.1 → Wireless Network → Security Settings

   The best option is - WPA2-PSK (AES)If it's worth it WPA3, try switching to WPA2 or mixed mode WPA2/WPA3.

2. Make sure there are no hidden characters in your password. Try re-entering it after copying it from Notepad.
3. Disable MAC filtering (if enabled) or add the MAC address of the problematic phone to the list of allowed ones.

On iPhone Sometimes resetting network settings helps:

Settings → General → Transfer or reset iPhone → Reset → Reset Network Settings

⚠️ Attention: After resetting your iPhone's network, you'll have to re-enter passwords for all saved Wi-Fi networks.

5. DNS and Routing Issues: Why Websites Won't Open

If the phone connects to Wi-Fi, but websites don't open, and messengers (for example, WhatsApp or Telegram) work - it's their fault DNS serversIt's like the internet's phone book: if it's unavailable, the browser doesn't know where to look.

Reasons:

• 🌍 The router or ISP is using broken DNS.
• 🔄 Incorrect DNS addresses were manually entered on the phone.
• 🛡️ The provider blocks DNS requests (typical for public networks).

Solutions:

1. Try manually entering DNS on your phone:
   • On Android: Settings → Wi-Fi → [Your network] → Change network → Show advanced settings → IP settings (Static) → DNS 1: 8.8.8.8, DNS 2: 8.8.4.4.
   • On iPhone: Settings → Wi-Fi → [Your network] → Configure DNS → Add server → 8.8.8.8, 1.1.1.1.

192.168.1.1 → Internet (WAN) → DNS settings

To check if DNS is working, open a browser on a non-working phone and enter the following into the address bar:

http://8.8.8.8

If the page doesn't open, the problem isn't with DNS, but with the connection itself. If it does open, the DNS servers are to blame.

6. Software failures: viruses, updates, and faulty firmware

If all the settings are correct, but the Internet on your phone still doesn’t work, the reason may be software failures:

• 🦠 Viruses or malicious applications, which block network traffic.
• 🔄 Failed OS update, after which the network drivers crashed.
• 📱 Custom firmware (for example, on Xiaomi or Samsung with root rights), where the network stack is incorrectly configured.

How to diagnose and treat:

1. Check your phone for viruses by using Malwarebytes or built-in antivirus (for example, Google Play Protect on Android).
2. Start your phone in safe mode:
   • On Android: Press and hold the power button → long tap on “Power off” → “Safe mode”.
   • On iPhone: When turning on, hold down the Volume Up button until the "Safe Mode" message appears.

If Wi-Fi works in safe mode, one of the installed applications is to blame.

⚠️ Attention: If the problem appeared after updating Android/iOS, check the support forums for your model (for example, 4PDA or Reddit). It's possible this is a widespread bug, and the manufacturer has already released a patch.

For Android-phones with root rights or custom firmware:

• Check the file /system/etc/hosts — sometimes there are website blocking rules written in there.
• Update network drivers through Magisk or TWRP.

7. Hardware problems: when a hardware failure is to blame

If none of the previous methods helped, the problem may be on hardware levelThis applies to phones that:

• 💥 Dropped or impacted (the Wi-Fi module is especially vulnerable).
• 🔥 Overheated (for example, charged under direct sunlight).
• 🛠️ Repaired with replacement of motherboard or antenna.

How to check:

1. Connect your phone to a different Wi-Fi network (for example, at a cafe or at a friend's place). If the problem persists, the phone is to blame.
2. Try connecting to Wi-Fi via modem mode (Share internet from another phone). If it doesn't work, there's a problem with the Wi-Fi module.
3. Check if it works Bluetooth And mobile InternetIf not, there is a problem with the antenna unit.

Solutions:

• 🔧 Contact a service center to have your Wi-Fi module diagnosed. The average repair cost ranges from 1,500 to 5,000 rubles (depending on the model).
• 📱 If your phone is under warranty, do not attempt to repair it yourself—this will void the warranty.

⚠️ Attention: on some models (eg, iPhone 11 or Samsung Galaxy S20The Wi-Fi module is integrated into the motherboard. Replacing it can cost half the phone.

8. Features of specific brands: Samsung, iPhone, Xiaomi, and others

Each manufacturer has its own quirks that can affect Wi-Fi performance. Let's look at the most common ones.

For iPhone the problem with is also relevant private Wi-Fi addresses (function Private Wi-Fi Address (in iOS 14+). It changes the device's MAC address to protect privacy, but some routers don't support it. To disable it:

Settings → Wi-Fi → [Your network] → Disable "Private Wi-Fi address"

On Android-phones (especially Samsung And OnePlus) disabling the function may help Auto-connection to open networks, which sometimes conflicts with home Wi-Fi.

FAQ: Frequently asked questions about the problem