You asked same question in another thread:
Just picked up a 22 Yukon Denali about a month ago but my Onstar/Navigation isn't working tried to call onstar they couldn't activate. Could It be an update or a problem with my onstar module? Questions- 1) Does anyone have a catch can or range technology AFM/DOD delete (Plugged inline with...
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Does your wireless data work? Ie your google maps on the infotainment system, etc?
Did you activate service with OnStar.
You are saying the symptom is no light on on the console?
Did you push the button, does it connect to OnStar, or say you don't have a plan?
Really, I think taking it to the dealer is the only option.