Every FM250 device uses two independent communication paths. Understanding which path has a problem is the first step in any troubleshooting scenario.

Quick Decision: Is the issue happening during on-site installation (likely Bluetooth or initial LTE setup), or was the device previously working and has stopped uploading data (likely LTE/cellular)? This determines where to start troubleshooting. 

How You Know There’s a Problem

You may have an LTE cellular issue if any of the following are true:

• On the Device: After pressing and holding the Play button for 3 seconds, the Wireless icon turns solid red and remains for approximately 30 seconds.
• WaterCompass Installer App: Connect via Bluetooth, then tap View Device. Cellular Connection shows “Fail” and no recent upload (Last Upload date is stale) or Signal Strength shows “Weak.”

Step 1: Check the Antenna Connection

• Verify the antenna cable is securely connected to the SMA connector on the device (hand-tight). Inspect the antenna and cable for any visible damage or kinks.
• After checking, press and hold the Play button for 3 seconds. Wait 1–2 minutes and watch for the LED to progress from yellow → green → solid green. If the Wireless icon turns solid green, the connection was successful.

Step 2: Perform a Visual Inspection of the Antenna and Cable

Conduct a thorough inspection of the antenna, antenna cable, connectors, and any extensions at the installation site:

• Is the antenna physically damaged? If yes, replace the antenna.
• Is the antenna cable physically damaged? If yes, replace the antenna.
• Is the antenna extension physically damaged (if applicable)? If yes, replace the extension only.
• Is the SMA connector corroded? If yes, the device must be replaced.

After addressing any physical issues, press and hold the Play button for 3 seconds and watch for solid green.

Step 3: Optimize Antenna Placement

• Confirm the antenna is mounted as high as possible within the installation environment. Remove any obstructions between the antenna and open air. If the device is installed in a meter vault, position the antenna as close to the vault opening or lid as possible using the antenna placement template.
• After repositioning, press and hold the Play button for 3 seconds. If the Wireless icon still turns solid red, continue to Step 4.

Step 4: Relocate or Extend the Antenna

• Try mounting the antenna in a different location within the installation environment. If a Wilson Cellular Network Test Kit is available, perform spot tests around the meter location to identify the strongest signal area before committing to a new mount point.
• If relocation improves the signal but the device cannot be moved to match, install an antenna extension cable to bridge the distance. For meter vault installations, this may involve excavating near the vault, drilling through the vault wall, and extending the cable to an antenna installed in an adjacent valve box above ground.
• After relocating or extending, press and hold the Play button for 3 seconds. Confirm the Wireless icon turns solid green. Then verify on the UltraSonix Dashboard that the device shows Online with an updated Last Upload timestamp.

Step 5: Run App Diagnostics to Confirm End-to-End Connectivity

• Connect to the device via Bluetooth, then navigate to View Device → three-dot menu (⋮) → Device Diagnostics. The expected result is Cellular Event = Ready and State Machines = (9,6,7) or (9,6,5). Capture a screenshot of the diagnostics results for the support record.
• After diagnostics complete, check the UltraSonix Dashboard. Connection Status should show the current upload time and signal strength at Medium or greater.

How You Know There's a Problem

You may have a Bluetooth issue if any of the following are true:

• The WaterCompass Installer App does not find the device serial number in the Bluetooth device list.
• The app shows “Not Connected” or fails to pair after selecting the device.
• The Wireless icon on the FM350 is not blinking blue, which would indicate Bluetooth advertising mode. 

Step 1: Confirm the Device is in Bluetooth Advertising Mode

• Press the Bluetooth button on the device once. The Wireless icon should begin blinking blue. If the icon does not respond, the device may be in Shipping Mode, mid-firmware update, or unresponsive. Refer to the Firmware Update in Progress or Stuck.
• After pressing the bluetooth button, open the WaterCompass Installer App and tap Connect. The device serial number should now appear now the list. 

Step 2: Check Proximity and Interference

• Ensure the phone or table is within 15 feet of the device. Confirm Bluetooth is enabled on the phone or tablet. If the device list does not refresh, close and reopen the WaterCompass Installer App.
• After checking, tap Connect in the app and select the device serial number. The app should show “Connected” and allow you to proceed.

Step 3: Cycle the Device Out of Cellular Mode

• If the device was recently in an LTE call (Play button was pressed), it may still be in cellular mode. Wait for the cellular cycle to complete (approximately 2 minutes), then press the Bluetooth button again. 
• The app should now see the device and connect successfully.

How you Know There's a Problem

A firmware update on the FM250 is indicated by the following LED combination:

• Play button LED: Solid Green
• Bluetooth button LED: Solid Red

A firmware update may appear stuck if the LEDs remain in the pattern for more than 15 minutes, or if the device does not respond to button presses after the expected update window. 

Step 1: Wait - Do not Press Any Buttons

• Firmware update can take up to 15 minutes to complete. Pressing buttons during an update will interrupt the process and can  cause device issues. Allow the full 15 minutes before taking further action. 
• After 15 minutes, press and hold the Play button for 3 seconds to check if the device responds normally. 

Step 2: Verify the Update Completed

• Press and hold the play button on the device to initiate LTE cellular communication.
• Connect to the device via Bluetooth and navigate to the View Device to check the communication status.