I had this problem in my Mark Viii, ended up being that when im done driving, the ignition key lock would rotate and release key and lock the shifter, but electronically would something was wrong. or it would be ok but then if the car bot bumped or the temperature changed or the gods were willing, the keylock would jiggle ever so slightly and set off the alarm. I would disable it and it would be quiet for a min, and go off again. only way to fix it was to jiggle the ignition lock violently. problem solved for a few more days....
It has something to do with your alarm 'accentuator' - contact Toyota about this since it might be a recalled item.
You can set the alarm off by just simply jumping on the car.
my alarm goes off at random times. i had the alarm module changed for $700 and it still goes off. come home from work at 4 and it goes off at 10. before the alarm module was changed it went off at 12, 2 and 4 in the morning.
someone or something to pass by it or touch it
A car alarm can go off with no one even near it. A bad earthing point or voltage change can make it go off. The sensor on the alarm itself may be too high which will cause it to go off with the lightest of touch.
Does it happen only while the car is "off" or does it also happen while driving? If the alarm happens without any apparent reason, even while driving, you may want to check the anti-theft relay. If alarm happens while the car is off, it could be a problem with any of the various switches and sensors that sense alarm conditions.
The likely reason why the alarm in a 1999 Lincoln Continental goes off on hot days is because warm air flow triggers the sensors. You can deactivate the alarm by unlocking the car.
If a person uses a key to unlock an alarmed vehicle, the alarm can be turned off on the 2000 Honda Civic LX by starting the car and putting it in gear. Then, put the car in park and shut the car off. Start the car again and the alarm should go off.
your speaking of the security system not battery if the battery is dead your system wouldn't come on now the problem is your alarm went off wouldn't shuit off so you shut it off on your keychain if not you disengaged the battery witch in turn fried your ecu unit that's what gives your car brains if in fact you tampered with electrobics or tried starting your car while the alarm was going off then the ecu could be dead
Thunder, rain, or defective sensor
Viper makes a car alarm that can be connected to your car's electrical power, which is then turned off upon triggering the alarm.
To turn off the car alarm on an Acura use your key to unlock the driver side door.