ORIGINAL: bonang

Its not the CD player that works with onstar its the harness you buy.

Copy and paste from a site:

Problem: Installing an aftermarket receiver in some 2000-up General Motors vehicles with OnStar means losing OnStar functions, as well as other audible safety warnings.
Solution: Metra's GMOS-01 GM data bus interface lets you replace the factory receiver in these vehicles while keeping OnStar, along with the door chime and audible safety warnings. Hook the GMOS-01 to your aftermarket radio, mount the module, and plug it into the existing factory plug. Get the great sound you want, and keep all important safety features intact. And you can adjust volume settings for OnStar as well as the safety chimes.

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Also, once you turn off the ignition in these GM vehicles, the radio continues to play until you open the door. This interface maintains that function with your new aftermarket radio. This interface is compatible with select 2001-and up GM vehicles. [/align][/align]