How-To: Changing Vcims GMT900.

mc7719 · December 3, 2010

Removed/replaced the VCIM in my '07 Sierra SLT (GMT900) equipped with steering wheel controls. The replacement is a VCIM module from an '09 or '10 with Bluetooth capability. At this time, it does disable the OnStar capability (red LED on mirror), as the module needs to be matched to the VIN on the vehicle by GM/OnStar. However, bluetooth capability works flawlessly and without any programming. Plug and play. I was never a OnStar subscriber, so this worked for me. By far the best mod I've done. But keep this in mind before you install.

This is bluetooth VCIM I used is part no. 20756237.

Also, make sure power is disabled while plugging and unplugging devices. I'm not responsible for any damage; physical, electrical, mental, or emotional, lol.

First remove center trim panel. (Image from service manual)

So, with the lack of a "flat-bladed plastic trim tool" (which it recommends) and to not damage the plastic with a screwdriver, I used a metal putty knife to get in there. A narrower putty knife would have worked better, but it was thin enough to pry up the plastic trim, while spreading the force over a wider area than a flat-bladed screwdriver would have done. The idea, is you can pry against the metal rather than the plastic trim. Once the metal blade is in there and pried up the trim, you should be able to get behind the metal blade, and pry against the plastic under the trim, and against the metal blade.

And these are the EIGHT clips the first image shows. They are in TIGHT.. you'll think that its not coming off, but it will. Be careful not to pry against the plastic trim with anything resembling a screwdriver. The plastic trim will give way (crack, etc.) before the clips do. Go slow working around the trim. (In the picture below on the right side, you'll see the marks on the plastic from the screwdriver prying out against the metal putty knife, but thats ok, as its covered by the silver frame.)

Undo the four bolts circled.

Unplug and remove the switch bar, and climate control unit. Most of these plugs are unique (i.e. they will only plug into one specific plug) and/or colour coded, so as to remember where they go during reassembly. Circled is the VCIM.

Its real tight for space in there but there are clips on the left, and right side of the metal box. One side at a time, push them out, and the unit will lift UP. Pull it forward, unplug the harnesses (keep in mind which is plugged in where (i.e. "J1" and J3"), and the two coax wires.

Side by side comparison. The new BT VCIM will have three coax plugs. One is for the BT antenna (tan coloured). make sure you connect it. The other two are are colour coded, and for the OnStar antenna.. (should there ever be a solution to get this feature working, you wont have to disassemble the dash again)

As you can see, the white VCIM plugs are on the opposite side and so its easier to flip the VCIM upside down (label down) to connect the plugs as noted earlier (J1, J3, etc.) Don't worry that there is four plugs in the old VCIM and three on the new one.

Clip the new VCIM back in. Turn on vehicle and test it out before you put everything together. Your mirror LED will be red, signaling OnStar is not connected. (The "emergency" button on your mirror may still connect to OnStar, not sure what happens otherwise) However, OnStar will not get signals from your vehicle, i.e. airbag deployment, diagnostics, and the such. (However if you don't pay for a subscription, you wouldn't get those abilities anyway) But feel free to give it a try.

Put your mobile device into pairing mode, turn BT on. Press and hold the steering wheel "Talk" button until you hear "Ready", then you say "Pair". Your device should recognize the vehicle and show "Handsfree" or "General Motors". I can't remember which one. Follow the instruction the magic box tells you to do, it will give you a code to connect the two.

When paired, have someone call you to test. Your vehicle should ring through the speakers, the incoming call phone number should appear on your Drivers Information Center. Press the "Talk" button on your steering wheel to connect. (Press the "Down Arrow" to disconnect. If all is working, reassemble reverse what you took apart. If something is not working, re-check all your cable connections.

If your truck is ringing, (i.e. an incoming call), and you answer by pressing the 'Answer' button on your DEVICE, the call will be routed through the device, and NOT through bluetooth. You need to answer the call via the truck (steering wheel control, or mirror button) for it to transmit through the truck.

Look up an owners manual from 2009 or '10 model to get the full instructions on how to operate the Bluetooth functions (record name tags, make/answer calls, use voice control/name recognition on your device, etc.)

Edited December 4, 2010 by mc7719

gobblerhuntr · December 3, 2010

What holds that VCIM in place?? BTW you are the man, pictures and all.

mc7719 · December 3, 2010

There are two clips on either side of the VCIM. I updated with an image.

dsch · December 22, 2010

What cant a dealer match the VCIM to the VIN?

1stimeyukon · January 4, 2011

im getting ready to do this later today but i have a question. where does the bluetooth antenna go? does it get routed like the gps antenna somewhere? thanks for the quick response

gonzo114 · January 10, 2011

Today I installed a VCIM that I bought off ebay. Install was a breeze using your instuctions, thanks. I can't get my DroidX to see it. Are there any other commands that are possible? A quick press of the voice button just mutes the radio and puts a voice icon on the nav screen. Holding it longer makes it ask for radio voice commands but it won't recognize me saying "pair".

Also, do you where I can find the procedure or list of commands to use and program #'s in when I do get it working? Thanks!

~kyle · January 10, 2011

Today I installed a VCIM that I bought off ebay. Install was a breeze using your instuctions, thanks. I can't get my DroidX to see it. Are there any other commands that are possible? A quick press of the voice button just mutes the radio and puts a voice icon on the nav screen. Holding it longer makes it ask for radio voice commands but it won't recognize me saying "pair".

Also, do you where I can find the procedure or list of commands to use and program #'s in when I do get it working? Thanks!

First press and hold the button for ~2 seconds, after the system says "Ready" say "Bluetooth", after the system says "Bluetooth ready" then say "Pair", then follow the instructions. The commands are listed in the owner's manual.

mc7719 · January 10, 2011

im getting ready to do this later today but i have a question. where does the bluetooth antenna go? does it get routed like the gps antenna somewhere? thanks for the quick response

The BT antenna is a small device plugged directly to the VCIM. See one of the pictures in the first post with it circled in blue.

gonzo114 · January 10, 2011

Today I installed a VCIM that I bought off ebay. Install was a breeze using your instuctions, thanks. I can't get my DroidX to see it. Are there any other commands that are possible? A quick press of the voice button just mutes the radio and puts a voice icon on the nav screen. Holding it longer makes it ask for radio voice commands but it won't recognize me saying "pair".

Also, do you where I can find the procedure or list of commands to use and program #'s in when I do get it working? Thanks!

First press and hold the button for ~2 seconds, after the system says "Ready" say "Bluetooth", after the system says "Bluetooth ready" then say "Pair", then follow the instructions. The commands are listed in the owner's manual.

Thanks for the tips. I got it paired now. My owners manual doesn't have the commands because the truck never came with bluetooth (2008). Can someone post the procedure to add #'s and use the bluetooth commands? Thanks.

~kyle · January 10, 2011

Thanks for the tips. I got it paired now. My owners manual doesn't have the commands because the truck never came with bluetooth (2008). Can someone post the procedure to add #'s and use the bluetooth commands? Thanks.

Strange, my '09 didn't come with bluetooth either but it's in my owner's manual. You can download the manual here, but if it's not in the '08 manual you can download the '09 to get the list.

Glad you got it paired up!

jdubub · January 10, 2011

Does anyone know with this option code that this is the right one? The part number is the same but on the site im loking at it just says this:

Item: Chassis Computer

Option: Communication (Onstar, opt UE1) ID 20756237

So im guessing since it is the right part number it will be the bluetooth as well...... can anyone confirm this?

Also it doesnt state anything about an antenna...... anyone know the part number i will need for the antenna?

It came out of a 2009 caddy DTS

THANKS

Item: Chassis Computer Option: Communication (OnStar, opt UE1) ID 20756237Item: Chassis Computer Option: Communication (OnStar, opt UE1) ID 20756237

Edited January 10, 2011 by JdubUB

~kyle · January 10, 2011

Part#20756237 is a bluetooth VCIM that should work, it's the one I have.

Part#15938939 is the bluetooth antenna you need if it's not included with the VCIM you're looking at.

jdubub · January 10, 2011

thank you sir! I need to order and get it in because my USB radio is waiting for me. A guy at the dealership got it for me and is going to re-program.... so i need to get it ordered and in fast before he does the new headunit and he can re-program my VCIM too for the onstar Mucho Gracias

mc7719 · January 10, 2011

thank you sir! I need to order and get it in because my USB radio is waiting for me. A guy at the dealership got it for me and is going to re-program.... so i need to get it ordered and in fast before he does the new headunit and he can re-program my VCIM too for the onstar Mucho Gracias

PLEASE let us know if you get the onStar working with the replacement VCIM. I don't think anyone has yet. For some reason they "can't" do it if the VCIM did not come with the vehicle from the factory. (But there's GOT to be a way)

mc7719 · January 10, 2011

Thanks for the tips. I got it paired now. My owners manual doesn't have the commands because the truck never came with bluetooth (2008). Can someone post the procedure to add #'s and use the bluetooth commands? Thanks.

Strange, my '09 didn't come with bluetooth either but it's in my owner's manual. You can download the manual here, but if it's not in the '08 manual you can download the '09 to get the list.

Its because it was an OPTION in '09, so its in your manual. It was never even offered as an option in 07/08.