Car Alarms: Car alarm goes off randomly, oem alarms, mitsubishi galant

Question
QUESTION: I have an '06 Mitsubishi Galant with 83,000 miles on it and
factory installed alarm.  My husband just changed one of my
oxygen sensors on Friday and since then my alarm has started
going off intermittently and randomly all hours of the day
and night.  Any correlation there?  My neighbors hate me.  
Please help.

ANSWER: Describe "going off".
(SIREN, FLASHING PARKING LIGHTS OR,
HEAD LIGHTS HONKING AND HEADLIGHTS FLASHING?)

Need more to go on so I can determine
the best course to take.

ALARMTEK
Tell neighbors to have patience.

---------- FOLLOW-UP ----------

QUESTION: Going off = flashing headlights, hazard lights and horn
honking.  

Answer
Ok, factory or OEM alarms depend on Battery drain to set
them off. Either from a door pin switch showing
the dome light on more then 10 seconds after closing.
Or, a bad or going bad battery. First thing is to
change out the battery to see if it's simply
reporting a low current, then if that does not
correct the issue, check each door and trunk
for an open ciruit (light on) or something plugged
into the lighted after you've turned off the car,
that sort of thing.

My money is on the battery thow.
Most of factory traced issues are simply
a bad power source.

To disarm it, put key in either door,
turn hard left, then hard right to disarm
and disable the OEM alarm. The factory remote will
do this as well.

I hope it does for yours too.

A.