PAC OS-311 Onstar Interface for 14 & 16 Pin GM Vehicles For GM's 14 and 16 pin Replaces factory radio in 2003-2006 GM SUVs and trucks Retains Onstar functions For GM's 14 and 16 pin Replaces factory radio in 20032006 GM SUVs and trucks Retains Onstar functions Pacos2/Pacos2 Bose communicate directly with the onstar module to prevent false Triggering and eliminating unwanted audio noise