I am AVIC Z1 user.
But I have already XM radio in my cadillac. Can I use this XM radio to Z1?

Short Answer: No

Long Answer: In theory, if you can determine what the audio out and control leads are for the factory xm, you could use it as a Aux input.

No you can't, however you can use the factory xm antenna for an aftermarket xm tuner.

cntrylvr79 said:

No you can't, however you can use the factory xm antenna for an aftermarket xm tuner.

Will the GM factory antenna work with the xm/nac traffic tuner??

Christopher said:

cntrylvr79 said:

No you can't, however you can use the factory xm antenna for an aftermarket xm tuner.

Will the GM factory antenna work with the xm/nac traffic tuner??

Yes. Use the yellow lead only.

I've made a little video about it showing detail in my GMC Canyon when I did it last summer (June) when I got the AVIC-D1.

http://web.ics.purdue.edu/~grajkovi/mov ... How-To.wmv

The video shows BOTH wires being used with the GEX-P910XM tuner, however I've since upgraded to the GEX-P10XMT and am only using the YELLOW wire.

Just connect the yellow wire. If your vehicle is different than the one shown then the location of the XM tuner may be different, however the procedure will be the same.

Good luck!

Thanks for the video!