Steve2150

Have a 2015 and want to add Nav again. I say again because I ordered the HMI from a vendor and while it worked perfectly it clashed with my onstar system giving me the red light and error not receiving onstar, whenever I called onstar they could not determine my location. Called the vendor and they were not able to fix it so I returned the HMI. Has anyone installed the Nav hmi and been able to use onstar also. Different vendors? or is the onstar module mated to the hmi.

dmaxx3500

and you use onstar for what,ive added nav to 2 c7 cars and a bunch of gm trucks,75% had onstar light afterwards,and 1/2 the light turned green after a few weeks

nobody knew why,and nobody really cared,because everything worked,[nav,gps,bluetooth]

Steve2150

Onstat was interferring with the GPS

Pickle1234

I was told you could add nav if it didn't come with Nav from the factory. Was told that it is hard wired to the radio /info system. Is that true