Avy 2008 swap out onstar for onstar with bluetooth module 8.1 (P/N 20787642)

Saw in a cadillac forum that they are having success swapping onstar modules out of 2008 or later cars with newer Onstar with Bluetooth modules.

They're getting full bluetooth functionality including phone numbers in DIC.

Will OnStar Bluetooth swap work for our Avy's?

Interesting idea, do you have a link to the post.

Thanks I'll look at it, it may work on the 07 up AVs. But probably will not of the 06 down

Found some stuff out for you not only can it work it have been done by a member Royal Vader I'll shoot him a PM

Got your PM, MS03.

This will be a lengthy post!

I'm pretty active over on the GM-Trucks forum, and this topic is HUGE right now.

Here's the thread: Start with post 34. Before that is junk.

http://www.gm-trucks.com/forums/index.php?showtopic=78031

It is a 30 page thread, but I'll summarize it for you:

This only applies to GMT900 trucks. The previous series trucks - GMT800 - 2006 and older are not included in this mod.

Basically guys that have 2007-2008 GMT900 trucks and SUV's (including our Avalanche) want to add OEM bluetooth functionality to their trucks. OEM bluetooth is available from GM on 2009+ model year vehicles including trucks. The bluetooth functionality is part of the Onstar VCIM module. Not all VCIM's are compatible with our GMT900's. There are three known GM part numbers that are compatible: 20783877, 20827036, and 25984444. You will also need the bluetooth antenna, which plugs into the back of the VCIM. P/N 15938939. The problem is - GM won't sell you a 2009 VCIM for a 2007-2008 truck. You have to give them your 2009+ VIN and one of 3 reasons why you are replacing it (fire, theft or failure). The only place to get one is from a dismantler or some are on eBay from time to time.

So, what's the problem?

1. The good news - Bluetooth works perfect! If you have steering wheel radio controls on your truck, your in business. You replace the VCIM (behind radio). Bluetooth pairing works great, voice commands work great and the phone number shows up on the DIC. All OEM and very sweet.

2. The BAD news - No one and I mean no one has been able to get Onstar to work with a newer VCIM in an older 2007-2008 truck. Onstar can't link your account to the new VCIM. The dealer has to do a re-learn with the TEC2 in order for the truck to recognize the new module. Supposedly, after the relearn, Onstar can just link your account to the new hardware. So far, Onstar tech folks have not been able to do this. There is some incompatibility flashing newer 2009+ firmware to a 2007-2008 truck. 

This is where all the effort is being spent right now. There are several vendors that claim they can hack the VCIM to fool Onstar into thinking it is an older VCIM, but no luck so far.

I'll post more as a solution comes up.

Thanks David.

When I was searching I found your post, there were a ton of post about this over there.

MS03 2500 said:

Thanks David.

When I was searching I found your post, there were a ton of post about this over there.

Click to expand...

Yea, it's pretty ugly right now.

Another pertinent link:

http://www.gm-trucks.com/forums/index.php?showtopic=78031&st=435&start=435

Ok, so to summarize. You CAN purchase a gen8 VCIM from a 2nd hand retailer such as a scrapyard, Ebay, etc (as GM will not sell it for a '08 or older vehicle), but you will lose all Onstar functionality. If we do not have Onstar to begin with then it is nothing to be concerned over.

If thats the case, I will begin looking in scrapyards for a VCIM with the part #s of 20783877, 20827036, or 25984444. Is it a difficult install?

Does anybody know where the OnStar module is in the 2008 Chevy Avalanche

Jvegas523 said:

Does anybody know where the OnStar module is in the 2008 Chevy Avalanche

Click to expand...

The Dark Lord says it's behind the radio.  I would be inclined to agree with him.  He may find your lack of faith disturbing...

I got a VCIM out of a used 2011 Silverado with voice control for my 2008 AVY. It came with a BT antenna for only 75 bucks.  Took out old VCIM and replaced and onstar and remote link both work but I have a red light on the right I assume because the new VCIM did not have a plug for the GPS connector that was on original.  SO the GPS stuff like virtual advisor will not work without the GPS.  After looking at other links I ordered a duplex splitter to hook up the GPS plug from GM Special Tools.  It should be here in a few days and I will let you know if it worked.  FYI  I also installed a navigation unit. EL-49903-3 is the part I ordered.

Have you thought about the BT and WIFI VCIM also.

The WIFI BT onstar is only in 2015 and 2016 so not sure if it would work  in my 2008.  Onstar would probably also charge a fortune to use it.

it worked... But...

I know its an old post but i just did the module swap out in my 07 Suburban and got the blue tooth to work just as indicated in this thread... BUT....  I have no clock display anymore, just  - - -  where the time should be. Any ideas why i cant put a time into this thing after a VCIM swap?

thanks
Ron

rpriz said:

I know its an old post but i just did the module swap out in my 07 Suburban and got the blue tooth to work just as indicated in this thread... BUT....  I have no clock display anymore, just  - - -  where the time should be. Any ideas why i cant put a time into this thing after a VCIM swap?

Click to expand...

Does it have Navigation with front LCD screen?

"Does it have Navigation with front LCD screen? "

yes it does

On my 2010 w/ nav anytime the battery is disconnected I have to enter the service menu of the radio to be able to set the time. After that, the clock works fine.

1. Press Menu
2. Press Display
3. Hold your finger on the imaginary button at the bottom left of the screen (still on the display menu)
4. Enter Code 295660
5. Press Next Page
6. Press Set time.
7. Set that time!

Let us know how your fair! 
Also, if a visual aid helps: https://www.youtube.com/watch?v=bZz3RK_kXgc

"Hold your finger on the imaginary button at the bottom left of the screen"


BINGO!!!  who would of ever know !  Thank you BAINMAN!!!!

Ron