Troubleshooting the Mesa 4 Cellular Modem

5 Nov 2024

The Mesa 4 uses the Sierra Wireless EM7590 Global modem. If the cellular modem isn't working, try the following troubleshooting suggestions.

Note: For additional help troubleshooting the cellular modem, contact support@junipersys.com.

Verify the Cellular Connection

After inserting the SIM card, wait five minutes to allow the cellular modem to detect the SIM card and load the carrier-specific firmware. Then, check the cellular connection in Settings.

Note: While the firmware loads, the cellular modem temporarily disappears from network and internet connections.

To verify the cellular connection in Settings,

  1. Open Settings and select Network & internet.
  2. Check for the cellular modem connection.

  1. If the cellular modem doesn't connect after five minutes, power off and on the tablet.

Power Off and On the Tablet

  1. Disconnect the tablet from external power.
  2. Power off the tablet by selecting Start > Power > Shut down.
  3. Wait for the display and red LED to turn off.
  4. Wait an additional 15 seconds for EC processes in the background to complete.
  5. Power on the tablet.
  6. If the cellular modem is still not working, restart the tablet by selecting Start > Power > Restart.

Update the Operating System

For best performance, update the Windows Operating System when a patch becomes available. To review recent updates to Mesa 4, view the release notes. 

Re-Enable the USB Composite Device

The cell modem is a USB composite device and appears in File Explorer as several devices, such as a network device, GNSS receiver, and comport device. If one or more of the sub-device drivers fails to load properly, the USB composite device can become disabled. 

To re-enable the USB composite device, 

  1. Select Start > Device Manager.

  2. Expand Universal serial bus controllers.

  3. Tap and hold the disabled USB composite device.

  1. Select Enable device from the menu.