Car Alarms: Mercury Cougar issue, 2000 mercury cougar, oem alarms

Question
My daughter bought a 2000 Mercury Cougar about 2 months ago. At some point throughout the night last night her interior dome light came on. She said it wasn't on when she parked it last night. Today she's at school and gets called down to the office that her car alarm is going off. She goes out to shut it off and then her car started beeping at her. I talked to a guy that I work with and he thought it may be something to do with the alarm system, maybe with the door, he told her not to lock her car and maybe that would get her through the day, we live in western PA and the temps now are around 20 degrees, and last night probably dropped in the low teens. I know that some times cold weather can affect things. Have you heard of this, and what are your thoughts? Thanks for help, Lisa

Answer
Ms. Lisa,
  Yes the alarm could be affected by cold as Factory/OEM
alarms detect and trigger by a percepitable battery drain of
5% or more.
(Unlikely the dome light comes on by itself, so maybe
a mistake was made there?) in any event, I'd like you to
replace the Battery all together to prevent this
from happening again. Not simply recharge the other, but
replace it with a fresh one.

I'll wager that that corrects the trouble.

Happens all the time, and this is how
you go about fixing it.

Good luck.

ALARMTEK