I have 2016 Suburban LTZ with no air moving out of rear roof AC Vents coming up on a Texas Summer!
It was working one day not working the next. I didn't hear any noises (was thinking the blower fan might make a noise if it was going bad)
Front dash AC is working fine.

What would be steps to do some basic troubleshooting? I am reasonably handy IT person who can do most things via YouTube but I am short on budget and would REALLY not like to have to pay for a repair! I haven't done anything yet but will look at it this weekend.

1. I assume there is a fuse for the blower motor?
2. No clue what to check next.

Thank you in advance!

 

of course. usually there's a map of the fuses on the bottom of the panel lid or in your manual.

https://charm.li/Chevy%20Truck/2013/...20Malfunction/

 

If the fuse for the rear blower is OK, then turn on the AC and check for positive voltage getting to the rear fan itself. If you're getting power there, suspect bad rear fan motor.

Sounds like you already have and know how to use a voltmeter !

I'd also check the owner's manual real well, as there could be on-off switch or switches for the rear air. Our 2014 Yukon has like a thousand buttons and switches !