Hi :)
My radio has no front sound ..with the radio or CD's...
as I fade rear.. rear gets louder
as I fade left... left rear gets louder
as I fade right...right rear gets louder
as I fade front... rear speakers get quieter then no sound
the only speakers working are the driver and passenger seat speakers
I have 25,000 miles on my XLR and the sound worked perfectly until a few days ago :)
Would this probably be an internal radio problem ????
any suggestions. thanks, ed :)

Depends. The CD changer is the main audio gateway in the XLR's "infotainment" system. For example, the navigation radio sends its left and right audio channels to the CD changer, which passes them to the seven-channel amplifier.

The CD changer also receives the left, right and common stereo lines from the S-Band (satellite) receiver.

The CD changer accepts operator inputs from the steering wheel control switches, including volume, pre-set seeking, etc.

Since you're getting both left and right channels, I would make the amplifier (or bad connection on one of it's outputs) my first check when troubleshooting.

One of the cool things about the Tech II is it's ability to measure and display the amplifier individual channel outputs to make troubleshooting a fault like this a snap.

Please let us know what fixes this so we can add it to the knowledge base.

CC :cheers

Hi Clarke :)
I went to the dealer and they plugged in their diagnostic computer..
the technician told me the BCM (body control module) is not communicating with the radio....
I wiggled the connections at the amplifier and BCM
and I disconnected my battery for 30 min to see if rebooting would help..
the dealership I go to lost their XLR tech and they won't work on my car now, they told me to go to another dealership.....
any other suggestions, thanks, ed :)

Sorry to hear about your dealership throwing in the towel over what is probably a pretty easy problem to diagnose. I fly home tonight and will check the books, and plug my Tech II into the system to see if I can come up with a troubleshooting path for you. Do you have access to a multi-meter?

CC :cheers

Hi :)
I really appreciate your help... and
I have a multi-meter :)
Let me know what I should do next, thanks, ed :)

Ed,

I was leaning toward the amp being bad (really easy to remove/install too) but after reading through the shop mauals, the Radio controls the Fade, Tone and Balance functions, so it's just, if not more suspect. Any dealership can use a Tech 2 to verify communications between the Radio and BCM. Pulling the Radio out and replacing it shouldn't be a big deal for them; I'm surprised they passed on the work.

By all means, take it to another dealership and have them take a crack at it. If it's the radio, you need a Tech 2 to do a VIN re-learn on the replacement. If they say it's the amp, you can replace that yourself, and save $200 buying it from gmpartsdirect.com.

I'd say the odds are 70% radio, 25% amplifier, and 5% something else. Let us know what fixes it so I can collect my winnings (or pay my debts!)

I'll be offline for the next couple of days as I pack up the house and move to CA.

Good luck to you!

CC:cheers

Hi Clarke :)
I am the guy whos front speakers quit working..
It was the amplifier,
I have a new amp now and not only do all speakers work, but..
the bass is much stronger now !!!!

I just had a buddy black out my grill, fog lights, head lights, tail lights and 3rd light in the rear... my XLR is now really all black, it is beautiful !!
I will take some pics and post them

I have owned many, many cars, I own 9 now... and my XLR is my favorite of all time !!

thanks, ed :)

Thanks for getting back to me with the fix Ed; I really appreciate it. I'm sure the amp was a lot cheaper than the radio to replace! Crank it up!

CC :cheers