2008 Silverado - Door Lock Relay/Solenoid?

My son just bought an 08 1500 Ext Cab. The power door locks do not work, not from the key fob remote, or either side of the two front door buttons.
But you can hear a click under the left side of the dash, like a relay, whenever you press any of the lock or unlock buttons on doors or key fob. So it sounds like it may possibly be a single relay or solenoid that is bad?
I searched through many posts on here, most were related to fob communication issues, BCM programming issues, or a single door, etc.
Thinking this is something different, just wondering if anyone can provide some guidance, or has access to a wiring diagram for an 08? Is there a single plug-in door lock relay on these trucks? If so, where is it located? I checked the fuse panels in-cab & underhood, found 1 Dr Lock fuse which is good. No relays marked Locks that I could see. It is quite a bit different than my 2002.

Thanks in advance for any help or advice!

Update - Turns out these trucks have a known issue with door lock actuator motors failing. We bought a pair of them online, (motors only), for about 1/4 the cost of new GM assemblies. The effort to replace them wasn't bad, once we figured out how to do it, (there were no instructions provided with the motors, but the website had some basic, not-very-useful text, with no pictures). The most difficult/time consuming part was drilling out the rivets to get the old motors out. Hard metal, the GM motors were German made. To install the new ones, we used some tiny, self-tapping screws from Lowes. Both sides have been working perfect for almost a year now. Wishing I would have made a YouTube video to help others out. Replacement motors around $50. Replacement GM assemblies were about $200, so it was worth the time to do it this way, for us. Also, the guy that sells the motors will install them in your old assemblies for about $100, which is better than replacement assemblies, if you can do without your truck for a couple weeks. If anyone has any questions, feel free to message me through here, or at dmoore454@aol.com