yankees9

I have read alot about this on here and other forums, but have not seen any that are in my situation. I have an 05 with navigation and no xm factory installed and no xm prewiring, I've already checked the wheel well. People are saying that you need a band button. The nav system as it is now has an fm1 button, fm2 button, am button, and cd button. I've seen the nav that has xm installed and they have fm1 and fm2 on the same button, xm1 and xm2 on another button. When I hook the sir-gm1 up will it switch this on my nav screen?

Thanks

shortski

I have an 05 Vert with the XM and installed the Sirius unit. I can't tell you how the screen works but I can tell you it will work. I pulled the instructions and with out the XM you use a T-Harness interface cable along with the included power harness with filter. Here's the wiring diagram. looks a little bit tougher because of the need to run the power harness back to the battery.

txjeep

Yankee,

Check the wheel well again very carefully. My factory XM harness was pushed out of the way and the connector was taped up so it wasn't very obvious. When I first looked for mine, I also thoght it wasn't there. You do have a coupe, right? The vert connector is under the waterfall between the seats.

I have the non-NAV Bose w/band button but no factory Xm tuner and my radio would not recognize the SIR-GM1. The good news for you is that others on this site have your exact setup and it seems to work for them. In your case, you will not have a band button. I think your NAV display will start displaying XM buttons when you hook up the tuner.

Good luck!

Whiterock1

Are you saying that all cars have the XM prewire whether or not XM is installed? I know that was the case for the 12 disc changer in Trans Ams. I just transferred my unit from my '97 to my 2000 and plugged it in.

txjeep

I am not sure if they all do, but mine does and I know others do as well. I suspect there is only one wiring harness used for all the C6s.

Radical05

This is what I observed on my install. Mine is pre wire however after the GM SIR install my XM buttons on the NAV were not displayed when the signal was sent. Hmmmm so I turned off the car and then turned it on again and it was there. Like a reset I guess. They will say XM but the channels are SIR. It does work. I have to say that the XM with its ant receives better. I'm using the SIR with the XM ant but when under lots of trees etc the signal drops out sometimes and that never happened with XM. SIR has better music that I like so oh well not a big deal and I dont stay under trees anyway.

yankees9

Thanks txjeep, After looking harder I did find the xm wire harness. It was pushed all the way back where I could barely reach it. I cut the electrical tape that was around it and it sprung loose. Installed my sir-gm1 in about 5 min. The buttons on the nav did change to xm1/xm2. Works like a charm. THANK YOU

'06 Quicksilver Z06

Nicely done.

I went through the exact same thing. Douldn't find thta harness without looking hard for it and found it taped to the inside wall of the rear quarter panel. Plugged it in and the NAV unit recognizes either an XM module or the SIR GM1.

txjeep

Glad to help. I am jealous of you though since you got yours to work and I did not. I am relegated to buying one of the plug and play tuners which is not really the route I wanted to go. Enjoy!