Why IoT Devices Fail To Connect to WiFi and How To Fix It

Why IoT Devices May Have Trouble Connecting To WiFi 2.4 / 5 GHz and How to Fix The Problem


Why IoT Devices Fail To Connect to WiFi and How To Fix It


So, you just picked up a new WiFi camera sensor, smoke detector, lock or smart switch but for some reason you just can't seem to connect it to your WiFi network.  Your device might be faulty then right?  Not necessarily.  There are some issues with the default settings used by many WiFi hubs and access points, including those supplied by major Internet providers. 

But never fear, we have some suggestions to help you get things working.

1. Most IoT gear only supports 2.4 GHz and your WiFi most like has both 2.4 GHz and 5 GHz

Many smart home devices—cameras, bulbs, plugs, sensors—use only the 2.4 GHz band because it offers better range and requires fewer radio components. These devices can't see or use 5 GHz networks at all.  Meanwhile many WiFi routers and access points offer both frequencies but prefer 5 GHz and both frequencies while operating separately often share the same name.  If your WiFi presents both 2.4 and 5 GHz bands under one name, the IoT device may get confused if it ends up with a 5 GHz beacon or setup association that doesn’t correspond to its supported band.   

2. Many devices are set up using a phone app

Many modern routers or mesh systems use band steering to automatically prefer 5 GHz-capable devices on that band to reduce congestion on 2.4 GHz. This is not standardized, so implementations can be poor and when you try to onboard a device via your phone, the router may steer your phone onto 5 GHz:

  • Phones almost always connect to the 5 GHz band so it “sees” the SSID on 5 GHz only

  • The IoT device, which only speaks 2.4 GHz, never sees the correct network info

  • Onboarding stalls or fails entirely.

3. Smart home apps often rely on captured Wi‑Fi details

During setup, apps may send the phone’s current BSSID (the radio MAC address) and band to the IoT device—so the device tries to join that exact instance. If that BSSID is on the 5 GHz radio, the 2.4 GHz-only device can’t use it. Many apps don’t check whether the device supports both bands. 

4. Wi‑Fi settings and router defaults can cause problems

Even beyond SSID and frequency issues, older IoT devices often don’t support newer security modes like WPA3/WPA2 mixed mode, advanced modulation schemes (e.g. Turbo QAM), or newer Wi-Fi standards.   When bands are merged, the router’s settings may default to something the IoT device can’t handle—even if the phone and laptop work fine. 


How to prevent or fix these connectivity problems

Use Separate SSIDs for 2.4 GHz and 5 GHz

The most reliable fix:

  1. Rename the bands with distinct network names (SSID), for example:

    • HomeWiFi_2G

    • HomeWiFi_5G

  2. During onboarding, ensure both your phone and the IoT device connect specifically to the 2.4 GHz SSID.

  3. After the device is set up, you can optionally merge again—but only if devices remain stable.  This ensures that the phone and device stay on the same band and prevents steering confusion.


Temporarily disable 5 GHz during setup

If your router doesn’t allow separate SSIDs:

  • Turn off the 5 GHz radio temporarily.

  • Connect your phone to the router, reducing it to 2.4 GHz mode.

  • Complete the onboarding process. Then turn 5 GHz back on once the device works.


Use a guest or IoT-only 2.4 GHz network

Some routers provide built-in guest or IoT network options that operate only on 2.4 GHz. These can be used during setup, even if your main SSID is shared. Once devices are onboarded, they continue using that 2.4 GHz-only SSID reliably. 


Set 2.4 GHz security mode to WPA2 only

If onboarding still fails:

  • Change the 2.4 GHz band’s security to WPA2 only, not WPA3/WPA2 mixed mode.

  • Make sure the IoT device supports the encryption in use.

  • Restart your network and retry the setup

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