I am upgrading a Hummer 2008 standard radio to the OEM navigation system, and I need to install the Antenna Assembly - GM (25918632). I have searched and searched... does anyone know where this mounts to? I cannot find the OEM mounting position. Thanks!

 

Mine is on the roof above the driver next to the sunroof

my truck has onstar also which may be why the antenna is different

I believe this antenna does both GPS and Onstar

GM 25775191

Neal

 

on trucks I've had to work on that type antenna its been mounted over the glovebox under the dash skin

Neal

 

Right... I am pretty sure that is where it is located on the H3... so I checked that location, and I can see the airbag, and then the mounting brackets for the grab bar above them... but I don't see a plate to mount the square GPS antenna. Maybe the mount is not provided with the UVA option, and only on the UVB option? I searched to the left of the radio opening, and don't see much. In the center top is where the dash speaker is mounted. to the top left, I don't see much. Then provided a photo behind the dash front-right, and all I see is the airbag at center and them mounts for the grab bar above.

 

This might help - drawings and part lists. You will need to pick the correct one though. I do know that first one shown on the passenger side roof with a small mast is an 03/04 only thing - those had the AM/FM antenna on the roof instead of the fender. Check the below link.

https://nemigaparts.com/cat_spares/epc/hummer/hm2-n/09/

 

@MixManSC - thanks so much... they had the diagram... it mounts under the Upper Dash Panel in front of the Driver. Makes sense so that it has a clear view through the windscreen. Here is the big question. My Upper Dash Panel, like most, has small cracks in it... and I am super hesitant to pull it out as that part is impossible to find a replacement for. It also has a ton of clips. Anyone have some advice on how to get the Upper Dash Panel out without cracking it? Is it even possible? Worst case I could just stick the antenna in an open spot under the dash and hope for reception... as I will really never actually use the navigation... just want to have the stock functionality in the H2. @HellHoof - had mentioned in another thread that he had reached out to Dorman to see if they would start manufacturing replacements, but not sure if they ever started. His photo of a completely cracked panel that he tried to remove from his Avalanche scared the Cr*p out of me!

Thoughts?

 

Pulling this back to the top - Anyone replace the GPS in a 2008/2009 H2? Do I need to pop the Upper Dash Panel off, or does it install some other way?

 

I had a New OEM NAV Radio installed and programed at the the dealer. They also replaced the NAV Antenna also. Not sure but I think you can get it in there without pulling the top dash, Mine is a 2009 SUV H2. On a side note. Be careful when unplugging that Antenna from the Radio. It's kind of a Funky connector.

 

OK - Finally got a weekend to continue the effort to convert my non-navigation 2008 H2 to a stock navigation unit (UVA to UVB conversion) and remove the GPS with a strikethrough from the display. What really paused this process was the need to remove that upper dash panel which has a crack in it and I was really hesitant to touch it. Finally got the courage.




Yes - The upper dash panel does need to be removed to install the Antenna Assembly - GM (25918632) which provides the compass function for the navigation unit. I found that the dash panel doesn't need to be fully removed... just the driver's side needs to be popped up enough to allow the antenna to be placed in the pocket and feed the wire down to the navigation unit.

What is needed to install the antenna:

• Pry tools - I have a Mictuning trim removal kit that was very handy. Getting those metal clips loose is very challenging. Do this on a warm day so the plastic is not brittle.
  • Small ratchet with 7mm small socket is required to mount the antenna to the dash. Since I did not pull the entire upper dash panel out, I used a low profile socket lever from PowerBuilt. No ratchet on that but let me squeeze in there.

Here is a quick overview on how to do it. This assumes you have already gotten the navigation unit installed and connected to Sirius XM. Now just need the compass to work.

First, get access to install the antenna:

• The drivers side A pillar trim and handle need to be removed.
• The fuse panel cover needs to be popped off.
• The navigation unit and trim needs to be carefully removed.

Next, the upper dash panel needs to be popped up to allow access to the antenna mounting pocket in the dash:

• There are 5 clips that hold the upper dash panel to the dash on the drivers side. Those need to be popped out.
• The first 2 clips are visible when the driver's door is open through a small opening in the dash. Instead of prying them up, I pushed them up from under the dash -- primarily to prevent further cracking the panel.
• The next three can be popped up using the flat plastic trim removal tool
• The antenna pocket will then be visible and empty to the right of the door lock receiver (25852909).

Then the antenna can be installed:

• There is one hex bolt there just waiting for an antenna to be bolted in. Remove that using a 7mm small socket.
• Place the antenna in just like the diagram above shows with flange towards the driver and cable towards the back right of the pocket.
• The antenna cable can be routed to the radio area by fishing it towards the rear of the pocket closer to the driver and to the right.
• Bolt the antenna in using that 7mm bolt. While the antenna plate has 4 mounting holes, I could only see one bolt to mount it. It was pretty secure with just that one bolt.

 

Nice Bruno,,excellent Layout and pictures....