Diagnostic menu for 2007 factory Nav?

[rudyo1]

How do you enable the diagnostic menu for the gps/ navigation on a 2007 factory unit?  I saw some posts for pre 2007 units, but the menu buttons they list dont appear on the 2007.

I am having trouble with my GPS icon having a red line through it indicating no gps signal. So I wanted to look at the diagnostic menu to see if it is even seeing satellites before I take it to the dealer.

Thanks

 

[Willyt]

There is a service bulletin out regarding this issue. The problem, most of the time, is the Onstar antenna is throwing a "shadow over the GPS antenna. This involves the 06 and 07 with the "Shark Fin Antenna. The first thing the bulletin tells the dealer to do is replace the Shark Fin antenna and if that doesn't fix it to replace the GPS antenna. My wife's Denali had this problem and the replacement shark fin antenna resolved the issue.

 

[Brewboy]

I have the same issue with my 07 Denali  build date 03/07, did anyone figure out the correct TSB or actually get instructions on how to get the diagnostic menu displayed?