I bought this 2006 H3 Base as a company vehicle for my automotive detailing and mobile electronics business... I had never done any mods to an H3 and neither had any of my installers, so we thought it'd be fun... We had no idea what we were getting into with the wonky electronics on these vehicles.

The security light was constantly on when we purchased it so this was the first problem we addressed. We went with a Fortin passlock sl2-v2-h3 module. But apparently it couldn't hold up to hummer's passlock resistance issues.

We ended up going with TechDoc 1603.
If you're having passlock issues I highly reccomend this as a $20 fix even if you aren't planning on installing a remote start - see the image.
GM's in the era of our hummer's only have 15 assigned resistances - see the image.

So far, I love the Hummer's look but I hate the electronic mess that lies beneath the beast.