Car Alarms: Mariano, siren, trumpet

Question
My alarm makes low sound when I activate it. It seem that I can't find the problem, need help with this!

Answer
My bet it is related to the siren or the grounds.

Check the siren first for water build up.
If waterlogged,
unscrew the siren from where it's mounted, drill a hole
through the trumpet part of the housing so you
can drain any water in it, and re attach.
Let dry completely and try again.

The other point is ground. Make sure the black wire
on the siren is grounded straight to the frame.

If all is good, should work as installed.

I hope this helps out.

ALARMTEK