MyGMC Trailer Light Test

I was hoping by now this would have been resolved but it appears that it hasn't so I feel inclined to voice my dissatisfaction of not having this feature.  It was a great selling feature when I purchased my 3500 HD Dully for the purpose of pulling trailers.  I have to always connect my trailer by myself and having the trailer light test allowed for me to test and ensure that all the lights were working properly.  Without this test feature it's just plug it in and hope everything is working properly.  There have been several time when there were issues with the plug connection that were easily found with this test.  You would think that both GM and OnStar would understand how much of a safety feature this function was making trailering safer for everyone on the road where lives count.  You have the software for the function already written so just put it back in the application.