I just purchased a new oem navigation unit for my 07 Tahoe. I installed the unit and at times I get a slash accross the GPS signal on the screen and tracking stops[]. Everything else works fine(radio, cd,sound)Has anyone had this problem? How can I fix this or does anyone know what it might be.?????

 

Welcome to the Tahoe forum. Maybe the connection to the GPS antenna is faulty.

 

I was just told I might need a VSS wire....does this make sense???

 

Could. Do you lose the GPS as soon as you start moving?

 

yes, and at times when I am moving>>>>>>>

 

I just noticed it also does not give me turn by turn directions, it just gives me the highlighted line with direction of travel.Could this be because ofthe vss wireas well?????

 

The Nav needs the VSS wire hooked up so when the GPS looses signal it still knows how far you have driven and how fast. That way it can still map you on the screen. Example under a row of dense trees, inside a tunnel or under a long bridge.
As far as not having turn by turn directions, either you need to turn it on in the menu options screen or you did not hook up the wire that goes to the VCIM (onstar receiver).

 

Great I will getthis VSS wire. Now as far and turn by turn, I do get the first voice command that says to follow the highlighted route and then get the voice command when I arrive at the location, by no turn by turn voice commands. Is this why I need this wire hooked up to the VCIM? Which wire is this and where does it go. THANKS!

 

poor design, 'add on' GPSs don't need a VSS wire... waste of a wire...

 

So I do not need this wire???? Is is just another GM malfunction?? This is normal......... Is anyone else having this issue with thier navigation unit that is stock?