well it may not be that simple, I think rather the BCM needs to be programmed for it to see the module correctly or perhaps both.An important discovery today - my remote start woes ARE related to my non-original t-case control module. We were on vacation over Thanksgiving week (not in the Tahoe) and I had a brainstorm: might as well try and swap back in the original control module to see if it changed anything. Got back last night and today I did the quick swap. Started right up with remote start. Tried it twice just to be sure. Swapped them back and not working again. So that's the problem, now to correct it....
I did the relearn procedure using my Tech 2 - that worked fine, but still no RS. Checked for any DTCs in the transfer case section of the Tech 2 - nothing. The only thing that seems amiss is the VIN code for the module obviously doesn't match the truck. So I'm guessing that is a trip to the dealer? I'm not sure I'm up for a software subscription and trying to get an old win 10 or XP computer up to the task so I can use the Tech 2 as a pass-through. Or is there a simpler method?
General agreement that correcting the VIN in the module will solve the problem? One thing that gives me pause is earlier in this thread, @Tozan confirmed that he did NOT have to reprogram the TCCM with correct VIN after he did the same swap as me (swap 2-speed t-case from 1-speed), and he still has working remote start. I don't know why mine is acting different, could be a programming change between his '11 and my '13.
which means you might have to request a specific calibration from techline/sps if it doesn't work from just letting it update thru sps.
I tried something similar on the Silverado I bought a upgraded radio module with built in nav to upgrade it from onstar nav, added everything needed, erased the old vin on the radio module and it worked, but it wasn't programmed to the vin correctly so I went and did the sps programming and it reverted it back to onstar nav so after some digging around I discovered that I would have to request a specific calibration to enable it thru sps but at that point I had already went with a different radio module and just let it be.