2002 Tahoe with the factory radio

I also need some help/  I have a 2002 Tahoe with the factory radio.  I want to be able to have the sound come from the factory speakers.  I purchased a 9 pin adapter that allows 2 rca inputs from pie that plugs into the factory wire as well as the factory 9 pin slot on the radio.  I was told that my car has a data bus system and I couldn't just hardwire into the speakers.  He told me I would need a hi/lo adapter so I purchased it as well.  I can not get it to work.  I know the adapter works because the other input runs my dvd player and it plays through the factory speakers just fine.  I would like to know which wires I would connect to the Hi level input.  The handsfree kit has 2 sets of wires comming from the harness....one is supposed to plug into the factory ISO adapter(female) in the radio and the other plugs into the ISO (male) connector going to the speakers.  I tried both sets and couldn't get any sound.  Any help would be great.  Thanks

I do not have the bose system.  I even tried to just connect to a speaker that I had in the shop.  I know the speaker works...I connected it to the black and the brown wires comming from the end that would normally run to the speakers in a vehicle that had iso connection.  I didn't have the other end of the harness plugged into anything (the iso connector that would plug into the radio) and I got no sound output.  The mic works on the hf kit because I can hear on the other line when I test the kit.  any suggestions?

HMMM I am by no means an expert with this stuff but I would assume that you need an amp(radio amp typically) and I would guess that it uses that signal and just changes it.   I dont think the unit has any actual power output.   I think that is the reason that you are not getting any sound.     Again this is just a guess but I dont see how it would output sound without some form of amp.     I could be wrong but I hope this helps.