I purchased my 2008 CTS at the end of October and while it did not have Bluetooth, it had all the other options I was looking for.
My 2008 was manufactured in March 08 and therefore has Gen 7 OnStar hardware.
I wanted to see if it was possible to add Bluetooth to the vehicle, without using aftermarket parts. I figured if I wasn't able to do it through the OnStar module, I'd buy a hands-free visor-mount Bluetooth speakerphone instead.
I bought a salvaged unit off eBay for $65 that came from a 2009 CTS. I found the device from Nordstrom's Automotive and is identified by
CADILLAC CTS 2009 Communication; (OnStar, opt UE1), w/voice recognition (opt UPF).
The model # is 25990227.
Before purchasing, I obtained a copy of the service manual and found that there weren’t any wiring changes that could cause a short or irreparable damage to both the module and my vehicle. I figured if the gen 8 module didn't work, I'd probably could plug the gen 7 module back in without problems.
I know that there was information about the new Bluetooth wiring provisions (WXS) when the Gen 8 Module was introduced. My guess is these wires were already part of the existing Nav system wiring (UQA, UQS), and were just separated into a separate wiring scheme in 2009 vehicles to allow Non-Nav cars to support Bluetooth as well (However, my guess is non-Nav cars might have this wiring too as OnStar runs through the stereo..... just don't take my word for it.) They provide a "Remote Playback Device Left Audio Signal", Mute, Ground and a "Cellular Microphone Signal" to the Nav System.
As mentioned, either my car already has it, or it's not needed as my Nav mutes when a call comes in, and I can hear the caller (and they can hear me) clearly when using Bluetooth.
The device arrived on Friday looks almost identical to the Gen 7 module. The only difference is it has a Bluetooth Connector / Antenna, as well as a Bluetooth logo and MAC address on the label.
Took me about an hour to remove the back seat, interior trim and rear shelf (as well as disable the airbags). At this point I had access to the module. I plugged the new one and turned on the car. Success! I went into the Hands-Free menu and said “Bluetooth” and it recognized it! I paired my phone and was able to make calls through the stereo. At this point my OnStar light was red, but probably because the device wasn’t connected long enough to get an OnStar and GPS signal.
Unfortunately, it took me 4 HOURS to remove the old module. Why? The old module is mounted to a plate and when I tried to loosen the nut holding down the module, the bolt turned as well.
I was unable to remove the tray as it was bolted down and one of the bolts had cap on it that couldn’t be removed (it had a wiring harness running through it, so I was unable to unscrew it).
I had to resort to taping a wrench to a paint stick and sliding it under the try to grab hold of the bolt. (There is a hole almost underneath the module in the trunk; however it was not large enough to place an object in to prevent the bolt from turning).
Anyways, although it took over 5 hours to do, I’m happy that it was successful. I will admit though I’m not sure if it’s a 100% success as there were a few problems that I outlined below:
Quirks
After installing the module and getting it mounted in the back of my vehicle, I turned my car onto accessory mode to verify the module worked before putting the car back together.
Unresolved Questions / Issues
My 2008 was manufactured in March 08 and therefore has Gen 7 OnStar hardware.
I wanted to see if it was possible to add Bluetooth to the vehicle, without using aftermarket parts. I figured if I wasn't able to do it through the OnStar module, I'd buy a hands-free visor-mount Bluetooth speakerphone instead.
I bought a salvaged unit off eBay for $65 that came from a 2009 CTS. I found the device from Nordstrom's Automotive and is identified by
CADILLAC CTS 2009 Communication; (OnStar, opt UE1), w/voice recognition (opt UPF).
The model # is 25990227.
Before purchasing, I obtained a copy of the service manual and found that there weren’t any wiring changes that could cause a short or irreparable damage to both the module and my vehicle. I figured if the gen 8 module didn't work, I'd probably could plug the gen 7 module back in without problems.
I know that there was information about the new Bluetooth wiring provisions (WXS) when the Gen 8 Module was introduced. My guess is these wires were already part of the existing Nav system wiring (UQA, UQS), and were just separated into a separate wiring scheme in 2009 vehicles to allow Non-Nav cars to support Bluetooth as well (However, my guess is non-Nav cars might have this wiring too as OnStar runs through the stereo..... just don't take my word for it.) They provide a "Remote Playback Device Left Audio Signal", Mute, Ground and a "Cellular Microphone Signal" to the Nav System.
As mentioned, either my car already has it, or it's not needed as my Nav mutes when a call comes in, and I can hear the caller (and they can hear me) clearly when using Bluetooth.
The device arrived on Friday looks almost identical to the Gen 7 module. The only difference is it has a Bluetooth Connector / Antenna, as well as a Bluetooth logo and MAC address on the label.
Took me about an hour to remove the back seat, interior trim and rear shelf (as well as disable the airbags). At this point I had access to the module. I plugged the new one and turned on the car. Success! I went into the Hands-Free menu and said “Bluetooth” and it recognized it! I paired my phone and was able to make calls through the stereo. At this point my OnStar light was red, but probably because the device wasn’t connected long enough to get an OnStar and GPS signal.
Unfortunately, it took me 4 HOURS to remove the old module. Why? The old module is mounted to a plate and when I tried to loosen the nut holding down the module, the bolt turned as well.
I was unable to remove the tray as it was bolted down and one of the bolts had cap on it that couldn’t be removed (it had a wiring harness running through it, so I was unable to unscrew it).
I had to resort to taping a wrench to a paint stick and sliding it under the try to grab hold of the bolt. (There is a hole almost underneath the module in the trunk; however it was not large enough to place an object in to prevent the bolt from turning).
Anyways, although it took over 5 hours to do, I’m happy that it was successful. I will admit though I’m not sure if it’s a 100% success as there were a few problems that I outlined below:
Quirks
After installing the module and getting it mounted in the back of my vehicle, I turned my car onto accessory mode to verify the module worked before putting the car back together.
- While the car was on accessory mode, my dash and Nav "restarted" and the DIC came up with the message "Stabilitrack Off". This is a total guess, but I wonder if it was due to the car detecting the new module, OR the battery was almost dead as I was in/out of the car for over 6 hours without starting it. To be safe I charged the battery overnight and it hasn't happened since.
- Also, on Sunday morning, my NAV display came up with the error that "the display unit is too hot and will shut down". This message disappeared after a few seconds and the Nav display is working fine.
Unresolved Questions / Issues
- When I have an incoming call, the Caller ID on the DIC shows "UNAVAILABLE". However, this may be due to the Bluetooth capabilities of the cell phone.
- Also, as this is a used module, I'm not sure if OnStar will be willing to reset the programming on the device to match my vehicle. Therefore, I don't know if I will be able to activate OnStar services on the vehicle. The good news is the OnStar light is green. I might look into it if I decide to activate OnStar in the New Year. There is a guy on the Silverado forums who said he called up OnStar and they downloaded the updated information about his car to the module. However, I'm unsure if he had a new, or a used module.