I still continue to use the Fusion site for software upgrades. I don't know for sure what Garmin is doing but they may have created a problem? If you have a problem with a software update Fusion tells you to call Garmin (possibly the software update they put out had a problem). To fix the CAN bus problem here is the Fusion response.
There have been reports of RV-IN801 vehicle settings being reset during a software update. To ensure correct operation, please do the following:
Check RV-IN801’s vehicle settings before starting your software update.
• Home > Settings > System > Use CAN Bus Message. Enabled for most Mercedes Sprinter installations
• Home > Settings > System > CAN Bus Mode: Direct or PSM; setting will depend on RV manufacturer and model year
• Home > Settings > System > Turn Cameras: Enabled or disabled, depending on if your vehicle is equipped with blind spot cameras that are viewed via the IN801
Always be sure that both VIM software and unit software are updated to the latest versions. After updating, confirm that the vehicle settings have been returned to their prior settings. If you are unsure of your original settings and there are any issues with the radio not properly receiving and acting on vehicle signals or unexpected behavior on other vehicle systems, do the following:
• Ensure that Use CAN Bus Message is enabled. Home > Settings > System > Use CAN Bus Message
• Try toggling the CAN Bus Mode. Home > Settings > System > CAN Bus Mode
If additional support is required after performing the steps listed above, please contact Garmin at 1-800-253-5081 or email at firstname.lastname@example.org