What are you using as a booster? I would make sure your booster has the proper amps. Recheck your connections, and try the inside hood release and the key fob hood release. I think if you don't have enough power, the computer sends the power to the more important things first i.e. the alarm system to keep a would be thief at bay. I would use a multimeter which you can buy at home depot for 10-15 bucks to make sure it's not too much power either (e.g. a battery from another car/truck.) My alarm went off as well, just remember key turns towards rear of car first, then front to disable alarm.

 

Well woo-hoo! I went out and bought a $10 set of jump leads hooked it up to my Vespa's battery and used the metal jacking point underneath the car for the negative connection (so I could keep the doors closed). The alarm went off and the key in the door (lock unlock) method still wouldn't switch the alarm off but the key fob just about found enough power to shut off the alarm. Popped the boot and gave the battery some juice and all is good the world.

 

I have a battery tender that hooks up to the battery. I did not know they make one to go into ciggerate lighter.