Car Alarms: fuel cut off, light flasher, impact sensor

Question
okay well my 2000 mustang was purchased 2nd hand by my sister before i purchased it from her a little over a yr ago, well when she got the car the remote didnt work they purchased a new battery still no luck, then the alarm would go off and cut off fuel supply so my sister disconnected the alarm welllll, im only 19yrs old female i feel safer with the alarm and i hate manually locking and unlocking my car esp when there is a alarm but they are to lazy to try to fix the problem soo if u have any advice please let me know what i can do to fix my alarm ps. i dont know what model the alarm is

Answer
This is a possibility of 3 different systems
on this car.

1.The noise generating and head light flashing system.
2.The PATS fuel cut off system (key transponder)
3.The chance there is an after market system
(siren and parking light flasher/shock impact sensor.)

If it's number 2, then you will need the 555fw bypass kit,
a relay and resistor to bypass it and keep it that way.
www.FORDPATS.com to get this accomplished.

If it's the last option, there would be a starter kill relay inline,
and there is a procedure involved to disable it.

And if numbe 1, this info is sold online at www.WIRINGCHARTS.com
and will eliminate this part of the equation.

Which applies to yours so I can advise?

ALARMTEK