: XM Radio disappears

12-19-05, 12:48 PM
I drove my 2006 CTS-V to the store yesterday, went inside to make my purchase and came back out 10 minutes later. Before I went into the store I was listening to one of the Christmas channels on XM. When I came out of the store and started the car up the radio was on FM.

So I push on the Band button of the NAV to get back to XM and there is no XM! Just FM1, FM2, and AM.

So I drive home with plans to take it to the dealer this morning and when I start up the car XM is back.

Has anyone else had similar problems?


Lindsay Cadillac
12-19-05, 12:52 PM
Sounds like a loose connection at the XM tuner. When you start the car the radio does a system test and if it doesn't see the tuner it won't display the XM band.

12-19-05, 12:55 PM
Where is the XM tuner?

Is it something I can check myself so I won't have to make the trip to the dealer?

Lindsay Cadillac
12-19-05, 01:00 PM
XM tuner is on the rear shelf. You have to remove the rear seat in order to access to it.

12-19-05, 01:01 PM
Its a PITA to get to. Its under the rear deck on the driver's side. There may also be a loose connection elsewhere besides the actual XM module.

If I were you I would wait for it to happen again, drive to the dealer, and show them that its missing on your BAND selection. This type of problem is extremely hard for a dealer to fix when you pull up to the service department and nothing is wrong at the moment (they will just turn you away, trust me). When you get to the dealer make sure you do not turn off the car so they can see that it is missing.

12-19-05, 01:06 PM
The XM tuner is on the driver's side mounted to the rear shelf.
Sometimes they don't get them plugged all the way in at the factory.
It's not impossible that the tuner could have an internal problem but since it went away and came back, it's probably just a bad connection.

Since it's under warranty, I'd let your dealership check it out. If anything breaks... well, it's better to let them break it.

12-19-05, 03:03 PM
Thanks for the advice.

I'll wait until (if) it does it again. Hopefully if it happens again it will happen in the morning and I can drive it straight to the dealer.

12-19-05, 04:13 PM
So if i go to the effort to get at it and unplug the wire the XM will dissapear from the Nav screen? Is that the only way to remove it?

12-19-05, 04:52 PM
I've seen where the presets on XM are gone and once where there was no sound for XM. In both cases the next time I drove the car everything was fine.

12-19-05, 05:37 PM
There are pictures and instruction on how to access the XM module in the faq:


Also, I have heard of this module losing connection with the radio (on the class II)... Intermittantly... When you restart the car you restart the module and communication resets (which is why it works again)... I would check the connector to make sure it is seated (expecially if you ever removed it, or adjusted it).

I think the daler can force the XM band to always be present on the Tech II (ewill, can you confirm).. That will make the XM band NOT disappear but you are still having communication issues...


12-19-05, 06:30 PM
Whenever you power up the Tech 2 and do what we call "build the vehicle" (tell the scan tool what you are working on) it does a communication check to see what modules are present.
It's set up to force a message if it doesn't see an XM tuner, it says "Digital Radio Receiver not responding".
If you can get it to act up this is the first thing they should check for.
As far as displaying on the radio, James is right. When the power mode master tells all the modules on the bus to power up they all send out a state of health message, if the XM receiver doesn't send out an SOH, the radio will not let you tune to the XM band. Once it starts recieving this SOH message it will work again.
If there is no SOH from the XM reciever it could be because of an internal software or hardware problem, or a poor connection or wiring problem.
On the base radios you have to go in and manually configure XM to work on the radio or it will just show am and fm when you scroll through the bands.
The nav radios have been plug and play, but I think the new touch screen ones require setup with the scan tool.
After the options are changed you have to turn the key off and wait a few minutes for the radio to "go to sleep" before it will power up again and learn the changes made with the scanner. Lots of guys skip this step when they replace radios and GM had to issue a TSB on it because so many people wouldn't have XM radio after their radio was replaced.

Removing the rear shelf is easy... and hard. It depends on what you are willing to do in order to disconnect it. Someone mentioned that, I'd think the only reason you would want to unhook it is so that you don't have to stop on XM when you switch bands because you don't want XM anymore. You can do that, but it's a pain. The sail panels have to come down and that's the trickiest part because they are so fragile.

11-21-07, 11:30 AM
I know this has been discussed long ago but I am having the same problem with Sirius ( I did the SIR GM1 swap), I noticed that if I toggle the memory 1-2 buttons a few times it appears back on but the preset channels all show 00 but they are still preset at their locations, Anyone else have the same show with the presets? I noticed it tends to happen more in the cold and when short trips are made with the car , This is really starting to pi$$ me off so I'd like to find a fix.

11-21-07, 01:47 PM
There is a TSB ( ID# 1798351 ) for 2005-2006 CTS-V's which covers that. If the digital radio receiver is other than P/N 15847358 it probably needs to be replaced.

Bob T
11-21-07, 07:07 PM
I periodically have the same problem and it always comes back. I think it is a transmission problem with XM so I would not tear the car apart looking for a problem that may not be there. When it goes out try turning the car off and then back on again, this sometimes fixes it too. Mine is never off for long

11-21-07, 07:55 PM
My 07 did this exact same thing this afternoon. I turned the car off and back on and it corrected itself.

11-21-07, 10:51 PM
Same happened to me yesterday. Has happened a couple of times in the past. I doubt it is a problem specific to your vehicle.

11-21-07, 11:12 PM
the same thing happened to me twice but first time xm admitted they cut off trial period 25 days early because they could not read a calendar i guess. so second time i immediately called them and they claim it was not them. it did come back 18 hours later after 4 or 5 restarts of the car. i am still not convinced it was not xm as same symptoms as when they cut it off but i would think it should access xm at all times just not play anyting but channel 1 test channel. if this happens again and i'm close to a dealer i will have them check tsb but not taking in while working as no result will happen. it is a pain but nice to see i'm not crazy like xm thinks.

11-22-07, 12:11 PM
I had that problem occasionally on my 04 w/ a Sirius GM-1.
I also had the problem on my 05 w/ the factory XM reciever.

It's very temporary and comes back after restarting the car combined with powering the Nav on/off.

I'd love to know of a difinitive fix as I need to install an iPod adapter soon, so I will have the rear shelf apart.

11-22-07, 04:25 PM
Same thing happened to mine, but it turned out that the module was bad. I removed the rear deck and reconnected everything myself before I took it in to no avail. First time getting everything off was a pain, but once you get a hang of it, it's not that bad.



11-22-07, 06:03 PM
Don't mean to take this thread of course, but how long of a plan can you get XM for. The reason I ask is that when I got the car used in Feb '06 the XM was on, and to this day hasn't been turned off. I haven't paid a dime and just figured that the previous owner had subscribed, but I'm surprised that its still going.

11-23-07, 05:06 AM
Don't mean to take this thread of course, but how long of a plan can you get XM for. The reason I ask is that when I got the car used in Feb '06 the XM was on, and to this day hasn't been turned off. I haven't paid a dime and just figured that the previous owner had subscribed, but I'm surprised that its still going.

Same thing happened to me...

I purchased the car used, and XM was on. While I already had an account with XM, I attempted to transfer my account to my recently purchased V.

They told me I couldn't transfer my account until the previous owner discontinued the service to the car.

That didn't happen until six months later... So much for trying to do "the right thing".

As for XM not appearing on ignition, I understand it's a faulty XM module. I have the same issue.

capt. dan
11-23-07, 12:01 PM
My XM had been disappearing since I had my car. Took a while before I had it happen when I could make it to the dealer to show them. They replaced th XM module and I still have the problem. I have not been able to make it to the dealer while it has happened. They wont do anything unless it is gone when you are there. This has been a PITA to get taken care of because it wont happen when your near the dealer.

11-23-07, 09:20 PM
XM would disappear on my '06 about once a month. Dealer diagnosed it as an internal failure with the XM receiver unit and replaced it right away. Work order says installed "receiver unit part #10373847 per NUL.#06-08-44-011B". That solved the disappearing XM problem, BUT then my XM Traffic wouldn't function. Took several visits to resolve that, but on instructions from TAC (???) they replaced the receiver again with an updated version and gave me the most current NAV disk. Never had anymore problems with it. Funny part was apparently they had never seen the XM Traffic service before. When I arrived to pick it up the salesmen were all playing with it.

I was really impressed with the time and effort the dealer (Ed Morse Cadillac in Brandon) put into resoving it. They never actually saw XM not working, but never questioned it when I said there was a problem.