Sirius is no longer an option on my list of audio sources.
Any thoughts as to why? I haven't been in the car to do anything and I have only had an oil change.
None of my settings were lost so I doubt the battery was disconnected.
Are there any other troubleshooting things I can do without ripping out the dash?
It could be caused by several things. I don't know how Sirius is provided to the Z-series, but if it's anything like my X910, the first I would look at is:
- the fuse providing power to the Sirius adapter blew
- Cabling to/from the Sirius adapter
- the power to the Sirius adapter
- the Sirius adapter went bad
I would think you'll have to open things up to figure it out.
Good luck - hope it's something simple
Did you really need anyone from the forum to tell you this? I mean, have you done anything to figure out the issue for yourself? When you have an issue like this, its usually pretty simple for anyone to figure out with just a little effort. 
I am not an installer. I don't install my own stuff.
I know I am not mechanically inclined so I leave it to the experts. I am pretty sure not everyone on this board does their own work. I wasn't aware that I was required to be a stereo installer to post a question on the board.
I did all I could think to do with in the interface, I was wondering if there was more that could be done besides factory reset, which is all I could find. Nothing like search for inputs or the like.
My apologies. If you can, certainly look over the things bobmaz listed. If you recently had this stuff installed, you should be able to return to your installer and have them fix it. If not, your probably looking at about 60 bucks to have it looked into and fixed. Provided its just a connection or fuse issue.
Do you know where the sirius tuner is installed? If you do, unplug the power and the P-bus cables at the tuner for a few seconds and then reconnect them. Had to do it myself once. If that doesn't work, try all the other stuff the previous poster listed
@VBlue42 - Accepted, we all have bad days.
@Camel - Yes, it was working for the past 6 months. My shop delayed me (had an installer go home which ticked off my wife who showed up at 10AM and was told to try again at 4PM) and then we forgot our apt. yesterday.
I will let yall know the result.