If you are planning to add factory XM to your car there are some important things to know before purchasing any of the components.
When I added XM to my vehicle, I purchased a new receiver from my local dealer. OEM XM receivers have TheftLock but it is independant of the TheftLock for the radio. While a dealer has the ability to unlock a radio, they cannot unlock an XM tuner. Here is an excerpt from the GM Service Information (eSI) system:
Digital Radio Receiver
The digital radio receiver utilizes class 2 serial data to determine if it is in the appropriate vehicle. Each time the digital radio receiver receives the "run" power mode message, it compares the VIN information received from a module which supplies VIN information on the class 2 serial data circuit. If a mis-match occurs, the radio display will indicate to the user the digital radio receiver is locked. The digital radio receiver cannot be unlocked, it must be replaced. The two scenarios able to cause this condition are:
1. A digital radio receiver is installed from another vehicle
2. A module which supplies VIN information is replaced and not properly setup with the correct VIN information for that vehicle
In speaking with users from some other GM forums, I understand that dealers had the ability to perform an XM receiver unlock until a Tech 2 scan tool software upgrade somewhere around the beginning of 2004. Since then, there is no menu option allowing dealers to do this. This is likely explained in the next paragraph.
When I contacted my local dealer to find the receiver, they were unable to locate the part number. On further research, I was told that XM receivers are a "restricted" part. There is a bulletin for dealers which outline specific procedures to obtain a REPLACEMENT tuner, but when they contacted the Technical Assistance Centre were told that these are otherwise not available. I thought this was odd so I contacted another dealer but was told the same thing. I then tried a US dealer since I wondered if this was because satellite radios were not permitted in Canadian cars until the 2006 model year. Regardless of which dealer I spoke with, I received basically the same response and they all seemed to have knowledge of this GM bulletin. I attempted to contact GM directly (instead of through my local dealer). I was told that this was a restriction XM Satellite put on these components, not GM. Of course when I spoke with them, they claimed to know nothing about this and referred me back to my dealer.
Interestingly enough, I obtained the part number of a tuner from a vehicle at a wrecker. I called a local dealer and asked if they could get the part and if so, how much it would be. When they checked the part number, the reply went something like "It'* a receiver of some type. We can order it and is $496.65". This is a CDN price by the way. Anyhow, this is one of those situations that make you say Hmmm.
In any event, I elected to purchase all new components (except for a mounting bracket which I bought from a wrecker). By the time I purchased the receiver, coax antenna cable, roof mount antenna, wiring harness connector, connector terminals and wire It cost me WAY more than I should have spent to add XM (>$1,000.00 CDN). I made the decision to stay original and even though it was expensive, I am much happier with its performance than what I had with any other aftermarket satellite radio. FYI, the first time a NEW OEM tuner is installed, it will learn the VIN for that vehicle. After that, if it is moved to another vehicle the TheftLock will activate.
What I found really frustrating is that GM sells an "Over The Counter" XM Radio kit for pick-up trucks and SUV'* but seem to have no interest at all in marketing such an item for cars. There is a TERK XMDGMK kit for GM vehicles which is supposed to seamlessly add XM functionality for cars. A Google search on "XMDGMK" will give you more information. This kit however isn't made for Bonnevilles due to the type of connector on the back of Bonneville radios. It also has a magnetic mount antenna like any of the aftermarket Add-On tuners, not like the OEM antenna.
The other consideration is that you will have to drill two holes in your roof for the antenna (if you decide to go fully OEM). Once I had the components, I called GM again to try and get the exact placment and size of the holes for the antenna. The customer service people told me that "Your car didn't come with XM radio. Even though this was a factory option for this car, since yours didn't come with it, it is considered a modification". They continued to tell me that GM doesn't support making modifications and refused to provide the information. I was also told "I'm not saying it will, but it could void your warranty". Don't get me wrong, I love my Bonneville but GM has made this very difficult every step of the way. I was able to obtain antenna placement information (with much appreciation) from another Bonneville Club member.
This is a doable project as I have proven, but no matter how you slice it you'll need to add wriing to your vehicle and spend what some may consider too much for the hardware.
StingRay Bike w/cards in the spokes, Weeeeeee!