I've read a few threads on this, but I'm still not 100% sure what the offending component is. If anyone can point me in the direction or help in further trouble shooting it would be appreciated.

The AUDIO, CLIMATE and OPTION buttons work and display the corresponding screens. The reverse camera works. The phone screen pops up, but no sound on phone calls. Otherwise, I have full audio sound. The navigation does not work at all.

Any ideas would be appreciated.

 

Check the navigation ECU that's in the trunk. It's located near the passenger rear. Check the connectors to make sure they are secure, no rusts, etc.

 

I don't know which threads you've read but this is where I've started: https://tinyurl.com/jrdhn8c

This thread contained one possible resolution: https://tinyurl.com/jbjdwpw

Good luck. If you resolve the issue please post back with your solution...