Is the antenna on the back window just for onstar or is it for onstar and the radio? Is there a hole through the window or is it just stuck on there with a glue of some sort?

The antenna on the rear window is the OnStar VOICE antenna. There is no hole through the glass. There is also an OnStar GPS antenna under the rear deck. One of the two radio antennas is on the rear window. It looks similar to the defrost grid but is across the top of the glass.

The antenna for the radio is in the front window where the blue sun-screen is.

Actually, the 2K+ Bonnevilles have a diversity antenna system. The one on the front glass is an FM only antenna. The one on the rear glass is AM/FM. The antenna module selects the correct antenna based on the band selected. When FM is selected, it phase matches the signal from the front and rear to provide the strongest possible signal. This is the basis of the diversity antenna.

There are soo many cool features on this car... I learn something new every day.

Thanks for the info.

Atleast I was 50% right.

Thanks for the info, I am gonna go ahead and remove the antenna for a cleaner look, I am never going to use onstar anyway.

Be careful around the defrost grid. When the dealer originally did my OnStar upgrade, they screwed up one of my traces when they used a razor blade to get the adhesive off the inside. The glass itself will scratch (they did this to the outside as well).

Very cool. I thought the front antenna was AM and the rear was FM.

Also the biscuit antenna on the roof is XM.

ddalder,

That is a fine explanation of a diversity antenna. Way to go. I have a new Altima in the family that has the diversity antenna and I was wondering how that thing worked. The reception in that and my Bonne is exceptional.

It'* a pretty cool system. There is actually even more to it than I mentioned, but it'* the basic concept. Delphi has also been working on developing a diversity antenna system for XM radio. The idea and test they've done have an XM antenna mounted in each door mirror. It'll be interesting to see if/when these start to hit the market.