Hello all,
I was wondering if anyone had a good link for a stereo wire diagram for a 2003 Hummer H2 I just purchased a aftermarket navigation stereo for my H2 and I can’t seem to find a good wire diagram.

Thank you very much for the help

 

Few try to directly wire stereo's anymore as it is generally desirable to keep the factory plugs for later reinstall of the factory stereo for resale and it is a LOT easier to make all of the connections on a workbench/table then just plug it in.

https://www.the12volt.com/installbay...Hummer/H2.html
This link shows a lot of various adapters and modules. Which you need depends on what, if any factory functionality you want to keep like Onstar, steering wheel controls, etc. You have a factory amplifier as well as a subwoofer under the floor console and if you plan on not using that then you have a much larger project as you will need to extend all of the speaker wires from floor under the console to the dash. Also certain factory functionality like the vehicle chimes are controlled through the factory stereo and if you want to retain all factory functions then you also need an interface module.

There are some other threads here on the forums you can find if you search that also have some wiring diagrams attached as well as posts from those who have gone the route of bypassing the factory amplifier. Also threads on aftermarket stereo while retaining other factory functions (what most do).

Another from the12volt - this one does give actual wiring info as well. https://www.the12volt.com/installbay/vehicles.html On this one you can find relevant info under Chevrolet, GM Vehicles, GMC, and Hummer. Basically from an electrical perspective an H2 is near identical to full size GM SUV's and trucks (Silverado, Tahoe, etc) with a few minor differences.

 

Thank you, I am using a scosche Gm2000sw interface I guess I didn’t word that right, but the wires on it are different colors than the harness. I wanted to see what the wires are and insure I had the right interface. Anyway I hooked it all up everything works but no sound and no steering wheel functions so either it’s the wrong interface or something else is wrong. The interface I bought doesn’t come with the smaller black plug it has 2 wires in it a orange and orange with a black stripe what those wires are I don’t know either. I’ll check out the links you posted I really appreciate the help. Thank you

 

Yeah, I checked the link only thing I saw was a for a 06 someone trying to wire to a door motor but no actual wire diagram showing what stereo wire does what. I couldn’t edit the post above I haven’t cut any wires and kept all harnesses intact so if I ever do sell my truck the new owner has the option to plug and play the factory stereo. Last stereo I put in was back in 1995 when things were easy😊

thanks again

 

take your time and read this from another forum . this covers anything you need to know .https://www.performancetrucks.net/fo...mt800s-496180/

 

Look @ post #6 in this thread.
You will NEVER have to worry about setting the parking brake to use any of the settings on the Alpine unit again.