Car unlocked but it sets the alarm ... car locked alarm goes for no obvious reason s type 4 liter.

Try resetting the alarm, using the instructions given at the link below. I'll also copy the text here.

1. Insert the ignition/door key in the door lock on the driver's- side door of your Mountaineer.
2. Turn the key to the lock position.
3. Turn your key to the unlock position.
4. Turn your key to the lock position.
5. Turn your key to the unlock position. Your alarm is now disabled. If your key fob works, you can also press the unlock or alarm-disable button on the fob.
6. Start the Mountaineer's engine and allow the vehicle to run for at least 10 minutes. This will allow the alarm to relearn the default settings. You must make sure that you have disabled the alarm first, however, before you attempt to start the vehicle, so that the alarm will reset itself.

http://www.ehow.com/how_5978302_reset-mercury-mountaineer-alarm.html


If these instructions don't work, you can try resetting the car's computer by unplugging the battery for half an hour. However, that will reset the keyless entry code, as you can see in the fixya article I link to at the bottom

http://www.fixya.com/cars/t4755856-we_bought_it_used_and_we_dont_know_the_k

If you just do not want the alarm sounding when locking unlocking the car find the alarm (horn ) and disconnect the wires to it

your car have a soon roof ? check if safe close

check key pad batt and read manual for reset instructiopns

some car alarms will go off if your battery is dying

NOT SURE IF THIS WORKS ON THIS MODEL (KINDA OLD FOR ME) HOWEVER TRY UNLOCKING PASSENGER SIDE DOOR TWICE TO RESET SYSTEM LET ME KNOW AND PLEASE RATE THIS

First to turn off the alarm you simply put the key into the drivers door and turn it to unlock the door twice, this is the factory setting to turn off activated Volkswagen alarm. As for the power locks they are air activated, in the trunk near the latch there should be a small electric motor that drives a small air pump with air lines running to all your locks. If this electric motor as worn out your locks will not operate, simple fix replace the motor. I'd try a used one first from a scrap yard to make sure but always check to see if there is power to the motor (you will need another person with a test light to perform this job). Let me know if this works. Vdubs 4-ever !

If your car has an alarm with a separate remote, it is a separate system and it is probably self-arming. When you lock the doors with the key central lock, the alarm gets armed by the RAV4 being OFF and the door locking action. When you unlock the doors with the key, the alarm is still armed because the key is not comunicating with the alarm just the cars factory keyless system.

the factory fit alarm is not voltage sensing .The best advice is to go to VW garage and get them to read the alarm causes,(they can check the last 4).this will give you a good idea where the fault lies.ie door lock mechanism,interior monitor etc..You cannot start looking for problem until you know alarm cause..

When a battery starts to go bad it will set the alarm off constantly. Check the date on your battery and if it's between 3 and 4 years old most likely this is the cause. I had it happen before.