I need some help. The last couple weeks when I lock the doors and set the alarm on my car, It goes off if a bus, my brother-law (open headers on his truck), or some other kind of loud vehicle goes by. It acts like it has a motion sensor, but it has never done this before. Any help will be appreciated.

 

there is actually a motion sensor in the trunk by the spare tire....if u take the cover off by the tire u will see a small piece that says security sensor, my car alarm goes off when ups trucks pass by.....

 

its actually a shock sensor. There is a little post on it where you can adjust the sensitivity on it.

 

Well, yesterday I go out to go to the store and the battery is dead. I replaced the battery, and the alarm is now the way it used to be. That is, it only goes off when you open the door with the key, and no longer when a vehicle goes by.

 

So a dying battery will cause your stock alarm to mess up? That might be my problem....cause my alarm is really agrivating me. I might go test the battery and see.

 

How ironic! Today I closed the hood on my SS ( in the normal fasion ) and the alarm went off. I said to myself "WTF?". That's never happened before and I haven't adjusted the sensitivity of the shock sensor. Didn't think anything of it at the time. My battery is not the greatest right now ( anyone else have bogus factory batteries? Should get the Dealer put a new one in before the warranty runs out. ) and will die out on my very quickly if the engine is not running. Was doing an electrical mod recently and put a meter on an 'always hot' wire and got a reading of only 10v DC from the battery. That's not good <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> .

Geeze, the things we learn eh?