question

Do you use the internal Bluetooth of the Cerbo?
There is a known issue with the BT module of the Cerbo it shuts off due to "high" temperature.
The FW update cause a higher CPU load and that can cause the BT module to crash.

You can try to turn off the Cerbo for a few minutes to let it cool down a bit.
But it is recommended to use an external BT dongle for a stable BT connection.

https://www.victronenergy.com/media/pg/Cerbo_GX/en/installation.html#UUID-572ae5ae-b9c9-b5a8-ea10-4940ba072b03_section-idm4637103287267232851365842652

I doubt it was heat causing the issue. The Bluetooth menu and sensors disappeared immediately upon upgrading to Venus OS 2.92. There was no time for the CPU to heat up and affect the internal Bluetooth. Additionally, I let the Cerbo run on Venus OS 2.92 for approximately 24 hrs. I then reverted back to v2.89 and my Bluetooth menu and options immediately came back. This is an obvious software issue, not a hardware issue.

An additional update. I let the system run on v2.89 for another 24 hrs after reverting and then did the v2.92 update again. This time everything worked and my Bluetooth menu and sensors are all there. I don’t know why it failed/disappeared the first time I tried to upgrade.

An additional update. Today I was checking my system status remotely through VRM to see how the solar was doing recharging the batteries. I noticed all my Ruuvi sensors hadn’t reported for about three hours. I pulled up remote console and went to the settings menu and couldn’t find the Bluetooth menu. It was completely gone from the menu structure again.

The last time this happened it was in conjunction with my upgrade to Venus OS 2.9.2 (as I reported above). This time there was no OS update involved. The Bluetooth just stopped working and disappeared from the menu structure for no apparent reason. I tried rebooting the Cerbo, but that didn’t solve the problem. I then reverted back to Venus OS 2.8.9. My Bluetooth menu came back, but the Cerbo still wasn’t seeing any of my Ruuvi sensors. I rebooted back to OS 2.9.2 and the Bluetooth menu disappeared again. I rebooted back to 2.8.9 and the menu came back, but still no sensors were present. I rebooted back to 2.9.2 and the Bluetooth menu disappeared again. I gave up and decided to mess with it some more when I got back to the trailer.

When we got back to the trailer a couple hours later, I checked the Cerbo and all my sensors were back showing in the Devices menu and my Bluetooth menu was back in the menu structure. I have no idea why it came back or why it disappeared. There were no changes to the system other than the passage of time.

Since this is an intermittent issue, I’m not sure what the best course of action would be to deal with it.