Well, I installed a Delphi touchscreen nav unit into my GMC Sierra. It originally had the Bose 6 disc in dash cd player. Everything works on the Delphi nav unit, except for the unit being able to read the navigation DVD. It tells me to make sure that it is a correct navigation DVD etc. The unit is a brand new unit from GM, sealed in the original box. It is the non-lux unit. It was made in mid 2005. I am trying to use a v4.1 disc, but even the earlier ones do not work, why?

Also, these should be compatible with all and any GM vehicle and should not be specific to Buick or GMC or Pontiac or Chevy, right? The disks shouls also work on any nav unit, right?

I know this is not fbody related, but I know many members here have TBSS's and Denalis with the touchscreen navigation. I know theres some techs on here as well that may be able to help me out.

Thanks in advance for the help.