Sync 3.4 not updating to 3.4.23088

Your APIM does not have a lot of free space.
Using Syn3updater, create a gracenote removal USB and run it against the unit, that should clear enough space for the upgrade to run.

But before running the upgrade, you need to create a new upgrade USB without gracenotes selected. That should install the build you want without issues.
Once that the system is upgraded, try running a new interrogator log to see how much free space the unit has. Maybe it will be enough for installing Gracenotes separately.

Use this thread as reference → Tutorial: Sync 3.4 NON-NAV APIM: Failure to Update to Newer Version Sync 3.4

Also, why do you have MY20 protection enabled?.
Do you suspect some component being MY20 on a 2017 car?

1 Like