tbarn

GM parts catalog.

It's the body shops problem. They are paid by the insurance company to fix your tuck.

Looks like there are only 2 options for seat back frame on '14- '18. With or without power recline. It would be quite expensive to buy 2 covers and 2 panels. Maybe $250 per seat.

84493319 Grille assembly without camera option. Should be correct but it would be better if you got a vin from a truck with the grille that you want.

Ha. I was going to post this info earlier today but he went to so much work and had such a nice post. I didn't want to bust his nuts😁

Welcome aboard.

The Tech2 is the best tool for GM for most all GM through 2009. 2010 started switching to GDS via computer/MDI interface. Trucks are good with Tech2 thru '13 for 1/2 ton and '14 for 3/4 ton. The main reason is it is bi-directional. You can turn evap solenoids on/off for example. Plus it works on abs, sir, entertainment and hvac. Tech2 is a no brainer for anybody with a GM vehicle on which it will work and has some mechanical/diagnostic abilities. These $250-350 Tech2's are Chinese knock off's but for the average Joe it wold be absolutely fine.

732 ohms open, 2312 ohms closed is the spec. Give or take some in real life.

The yellow wire is for Hybrid vehicles. Otherwise not used.

There are 2018's with the hard back cover. In the parts catalog it shows both. Not sure why they have both. Probably depends on option packages or could be seat/truck build location. Either way I don't see you just adding the panel. Covers are different as are the frames, probably.

All the 5.3's use the same ecm. At least for 2011 pick up trucks. P/N 12633238 although probably different programming.

Try a local dealer.

For $25 or so you can get a factory harness and modify the ends on each side to fit what ever you are doing. You'll get a better terminal seal under the vehicle. P/N 23327843 https://www.gmpartsdirect.com/oem-parts/gm-wire-harness-23327843

At this point it appears you have two options. Return or exchage the fob or take the truck and all fobs to a dealer and have them try it using GM SPS system. It will cost whether it works or not though. Getting a new bad fob is not all that rare.

Is your vehicle under 3/36 bumper to bumper warranty? One of your free oil changes? GM's multi-point inspection is not required for warranty purposes. Nor should you be charged for it. It is meant for up sell purposes. Unless something is found wrong that is under warranty, then it's usually a battle to get a service manager to sign off for the repair. I've had coolant leaks that I've found that were denied because the customer didn't complain of a leak.