no because the car would povide a shield around the alarm. the only way i can think of that you might be able to zap somthing that way would require a lightning bolt right down the antenna of the alarm brain.
ive seen the question asked before about could you rig up some way to zap someone if they touched the car.
and here is the scoop.
it would be possible to zap someone if they touched the car with the alarm going off but you would have to have some way to connect a ground wire to the ground they are standing on. then connect a high voltage coil like one used for spark plugs and connect that to the frame of the car.
if the person and the conductor under the car were both grounded well enough it might work. but i would not want to be the one testing it out.