I have an 06 Silverado extended cab it does have Onstar but im not sure if it has a boss system ive changed the 2 front speakers but I need to know that if I install an aftermarket radio will i need a wiring harness to be able to still use onstar and all my dash signals(check engine light, seat belt, check oil,etc.)?
Yes you'll need the harness thyll run about +$80 and yes the check engines light,open door chimes,ignition light,warning frm passanger airbag,cluster gas gauge,low fuel warning,rpm gauge,on star,and yur bose amp if u have it, will all STOP working if u DO NOT use the interface HARNESS:)
