what..?????

 

The OnStar unit is not controlling your door locks or alarm - it simply sends commands to the vehicle to lock/unlock.

It sounds like your roof lights leaked, allowing water to get into the center console. As for how that set off the alarm - I would suspect the front drivers corner light leaked and water got down by all the wiring by your drivers footwell.

The horn is on the right side, at the far front of the truck, but not on the hood, as I remember. Try jumping that straight to your battery to see if it works - or disconnect it, hook a volt meter to the wiring, and have a friend push the horn in the truck to see if you get voltage.

 

My H2 actually has two horns. One on the driver's side and one on the passenger side. I pulled the wiring harness off and tested each one for voltage when the horn was pushed on the steering. The one on the driver's side does nothing, and the one on the passenger side did indeed give me 12 volts when pushed. Maybe the horn on the driver's side is for the security, so that's why pushing the horn didn't show any voltage there?

I ordered a new set of horns and will install the one on the passenger side first and see what happens when I set the alarm. That should at least get me my horn back, but if the security still doesn't beep, I'm going to assume both horns were simply dead and swap out the driver's side too and see if that fixes the lack of a security horn.

It just seems odd that both horns would go out at the same time? Maybe the fact that they were stuck in the "on" position shorted them both out together and that's my problem? They beeped for about 30 mins and eventually just stopped. I would have disconnected the battery, but it was during a nasty storm, and I wasn't going out in a pouring monsoon to disconnect it. I'm just guessing, but maybe the two horns are for separate things? Maybe one is for security and the other is for the actual car horn? I will report back on what I come up with for anyone that might have this same issue in the future.