I realize this might be a stupid question for more experienced Hummer owners, so please bear with me. I just got an '06 H3 with Monsoon. Upgrading fr stock to a Kenwood double din touch screen stereo. Do I absolutely need to use a wiring harness, or can I patch directly to the existing wiring like I've done on other vehicles? It has OnStar, but we aren't going to use it. Thanks in advance for any input.

 

Just save a little $ and buy the GMOS-04. Plug and Play.
Hacking the factory wiring is just asking for issues.

 

I agree with Tainter, don't hack things up. You also lose the chimes (door open, lights on etc) if you don't use an interface.

 

Plus it would go a lot faster and smoother with the interface.

 

Thanks guys, this is what I figured. Just wanted to be 100% sure. I appreciate the input.

 

You can purchase a Metra harness that is about $10. Wait a minute LoL I've got one in my spare Hummer draw of goodies that you can have for cheap.

It is literally a basic harness NO frills.

 

Agreed, why hack up wires and risk a short circuit. Do the interface and be safe...

 

Yeah right!
Show me this "Metra harness that is about $10" for an H3 with the Monsoon.

 

TRUE!!! = There is No $10 harness for the H3 with Monsoon
I just paid $90.00 on Amazon for the Monsoon wire harness.

 

I would just bring it in if you want it done right. I got a Kenwood connected with the monsoon amp and added door speakers and a 8inch kicker sub in the back and i love it. I mean it sounds like you want to connect to the amp??? I know the installer had to by a few different pieces to get the stereo connected on my h3. I had them put a remote start and stereo and back up camera and the h3 is like it’s a 2019 vehicle now. But it’s was pricey $900