First Alert SC5 WiFi Connection Problems Exploreod

First Alert SC5 Won't Connect to Wi-Fi


The First Alert SC5 needs to connect to your WiFi network.  It supports both 2.4 GHz and 5 GHz networks, however there may be issues caused by the set up of your WiFi router or access point.  Here are some suggestions to try to resolve the issue.  I

1. WiFi networks often use a unified SSID (network name) 

By default, many WiFi routers, access points and modems from Internet providers use the same name for both 2.4 GHz and 5 GHz networks.  This can cause the SC5 to get confused during the initial connection.

2. Phones Connect to 5 Ghz by default

Often the WiFi network prefers a 5 GHz connection by using something called Band Steering.  Often this band steering is not well implemented as it's not a true WiFi standard.

During setup, apps may send the phone’s BSSID (the radio MAC address) and band to the SC5, but if the device tries to join the a different band, it can cause issues.

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. 


What Can You Do?

We recommend setting up WiFi to Use Separate Names for 2.4 GHz and 5 GHz

The most reliable fix to resolve issues caused by mixed 2.4 GHz and 5 GHz networks is to name each network differently.  So for example change the 2.4 GHz name to MyWiFi2G and the 5 GHz name to MyWiFi5G.  Then you should be able to connect your phone and the SC5 to the same frequency.   2.4 GHz may be preferred here.

Temporarily disable 5 GHz during setup

  • 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

Many WiFi networks offer a separate and built-in guest or IoT network that operates at 2.4 GHz.   Connect your phone to this network during set up so your SC5 will be connected to the 2.4 GHz IoT network.  Then you can switch your phone back to the main network after you're done.

Set 2.4 GHz security mode to WPA2 only

If you're still having trouble, try to change your 2.4 GHz WiFi band security to WPA2 only, not WPA3/WPA2 mixed mode.  It's possible that there are issues with the WPA3 version or implementation that are causing a problem. 


Additional guidance may be found here:


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