Car Alarms: Car Alarm is Malfunctioning, dodge grand caravan, flip switch

Question
QUESTION: I have a 2000 Dodge Grand Caravan and recently had the transmission replaced. The battery was disconnected and now that it is hooked back up the alarm system is malfunctioning. I do not have the remote for it. The only way to disable the alarm is to drive with the headlights on and when it is turned off, disconnect the battery. The dealership states that when hooked up to the computer the alarm system is "disarmed". The lights go on and off for 20 seconds, shut down for 10 seconds and then start again. How do I disable the alarm system?
ANSWER: Is this an aftermarket alarm system?  If it is, take a look under the driver's dashboard and find the brain of the system.  Post back the exact make and model of the alarm and I will see what I can do about finding you an owner's manual for it.  Most aftermarket alarms have a way to disable them manually.  There should be a small toggle/flip switch under the driver's side dash that when pushed with the key in the run position should disable the system.  If the dealership is saying the factory alarm is reading disarmed then I would have to think there is an aftermarket system in there as well.

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QUESTION: I found the remote that came with the van. I was never told there was an alarm system, yet Chrysler is telling me that it is a factory installed alarm. I hit the unlock button and the lights stopped flashing. My mechanic and the dealership could not find an aftermarket system. We also could not find a toggle/flip switch to turn it off. How do I arm the alarm system and will this cause future problems?

Answer
If this is a factory keyfob that stopped the lights from flashing then just pressing lock and unlock on the remote will arm and disarm the alarm.  My concern is that if it is indeed the factory alarm you were having problems with then unlocking the door with a key should have also disarmed the alarm.  A factory alarm will not have a valet/toggle switch under the dash as the key in the door will control the manual disarm/override.