Car Alarms: My 2005 Nissan Altima Car alarm system, 2005 nissan altima, car alarm system

Question
Hi I bought my car 1 month ago, today i went to the gas station and i had power locked all the doors and right before closing the driver side door i unlocked it before closing. Once i got back to the car, i opened the door and the car alarm went off. On my key chain i dont have an alarm pad??, i tried everything, and i can't figure out how to shut the alarm off. It finally shut off and i drove to work. When i got to work I went to open the door the alarm went off again, it shut off again eventually, however i dont have the car manual, only the maintenance book....Can you help me solve this problem?

Thanks!

Cindy

Answer
Please be more descriptive if possible.

"GOING OFF?"

I need to determine whether it's a factory alarm
issue or, if it's an aftermarket system you are
dealing with.

Is it: Headlights flashing, car horn honking
and a worded SECURITY" light in the dash flashing?
(doubtfull since none of the notes show this
car as having a factory alarm system)=FACTORY

Or,

is it: flashing parking lights,
an LED in the dash area, and a siren
going off?= AFTER MARKET

Let me know more on this to better
advise you on a course of action
to take.

Best Regards,

Robert Martin
CEO/ALARMTEK
CARALARMMAN.com