Car Alarms: Car alarm goes off, car wont start, mercury mountaineer, spark 2

Question
QUESTION: Hello:
I have a Mercury Mountaineer 2002. It didn't turn on so I got the car jumped and it turn on. Later on same thing happened, so the mechanic said is the battery but the alarm control doesn't work and the alarm is going off on an on.
I'm afraid it will kill the battery again ( I bought a new one)some people said I have to disconnect the alarm, other said it just the alarm control battery. Please advise
Thank you

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.

Ok let's clear up the terminology glitch here.

1. FACTORY/OEM alarm = Part of the original schematics
and plans from the manufacturer.
(horn honk, head lights flash, Starter may crank and
die, no spark)

2. DEALER INSTALLED alarm = Just that. Once the vehicle
is brought to a dealer, the dealer sub contracts the after market
security out.
(horn might honk, siren and parking lights flash, starter kill relya,
no start, no crank, just dead.)

3. AFTER MARKET alarm: Same as #2 but Customer IS AWARE that
the system was put in at the dealership, but may not
be informed of the brand name, or even what it's
total capabilities are.
(siren & parking lights flash, starter kill)

Which one applies to yours?

RM/ALARMTEK
CARALARMMAN.COM

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

QUESTION: tk u for ur quick response. It's a factory alarm. Looks like the alarm was turning on by itself until the battery died. I couldn't turn it on. After it got jumped it didn't turn on immediately, it was making some crank noise after probable 5 minutes the carturn on. Later that same day got dead again. So I called the mechanic and he said it was a battery problem. I had to buy a new one. But today in the morning while the car being parked the alarm turn on again. so I'm afraid that it will eat the battery again. I don't if this info is ok. Let me know if you need more details.
tk u so much.I really appreciated.  

Answer
Ok, I don't think this is a security issue in that,
it appears the alarm is reacting to an open circuit
and reporting the drain that is being placed on the battery.

That's symptomatic of a deeper issue.
Maybe a PATS or BCM situation or,
a bad module in the truck.

Things do happen. But from the reaction
and the constant batter issue, I'd look
deeper into this past the security issue
for your trouble spot.

RM