Onstar antenna - Does it also have an XM radio plug?

[Blast Chamber]

My 2008 Vibe came with Onstar but not factory XM. The Onstar antenna is on the roof next to the standard radio antenna. I have an XM Roady2 receiver in the car and it's XM antenna sitting on the dash. My question is does the Onstar antenna also serve as an XM antenna for those who have both OEM options (2 plugs)? My Onstar antenna looks similar to the one in the eBay auction, that does have capabilities to do both.I'm hoping that I can run an antenna cable from my Roady2 up to this Onstar antenna and connect it to an unused plug. Anyone who has both Onstar and XM from the factory, can you comment on the antenna setup?Thanks!http://cgi.ebay.com/ebaymotors...ZWDVW

[breezd]

Off track... but just saw that you were from WI! Welcome to the forums. Good to have another WI member!And now hopefully someone else can help with your question...

[Blast Chamber]

Thanks, breezd. I sure see a lot of Vibes here in SE Wisconsin.I think I've answered my own question about the antenna. I peeked under the headliner in back and see the antenna has 3 wires coming from it, with two of them currently in use by Onstar. The unused wire has a male SMB plug on the end, which must be for XM. I'm going to buy a Female SMB to Female SMB adapter and a 20' extension cable and run it up to my Roady2. I'll post how it works out after I complete the install and testing.

[breezd]

Good luck and be sure to post your findings!

[Blast Chamber]

Well, the results and in, and the operation was a complete success. The Onstar antenna on my 2008 model also has XM capabilities.I purchased the following items to make my add-on Roady2 receiver work with the on-roof antenna....www.myradiostore.com1 - 20' Antenna Extension for $23.98 including shippinghttp://www.smelectronics.us1 - SM2007 SMB Female to SMB Female Adapter Plug for $22.50 including shippingRunning the antenna wire extension from the rear roof, down the rear-passenger side panel, and under the carpet to the front was the toughest part as the antenna wire is thin and very fragile. With patience it is possible to fish the wire through the gaps, and 20' is plenty for a Vibe. Signal is good, and the ugly magnetic antenna is now gone from my dashboard. If you're wondering why I didn't just route the Roady's magnetic antenna outside to the roof, I did that on my vehicle before the Vibe, and it only lasted 2 weeks before something shorted out. The dash setup worked fine unless driving directly north while going downhill.