When changing a new battery the alarm automatically activate when connecting the terminals please tell me how to de-activate. Haynes manual it said there is a switch under the dashboard but i can't find it

The alarm system needs to be de-activated by turning the key to the unlock position at the drivers door lock cylinder when re-connecting the battery. The alarm control module cannot be disconnected otherwise the vehicle will not start.

On some models you can disable the alarm after you connect the battery by locking and unlocking the driver door with the key.
I would disconnect the horn or pull the relay until you can get the alarm turned off.

maybe a haynes repair manual would help.check your auto parts store or on ebay

The car alarm on your 2000 Windstar minivan is wired into your van's battery. When you are making a repair to your car such as a battery change out your alarm can go off. You can easily disable the Windstar's car alarm by disconnecting the battery from the alarm. The battery is connected to the Windstar battery's negative terminal. Disconnecting the terminal from the battery will disable the alarm.

• Socket wrench

1. 1 Raise the hood of the Windstar to gain access to the battery.
   
2. 2 Loosen the negative battery terminal labeled with a "-" with a socket wrench.
   
3. 3 Disconnect the terminal from the battery to disable the alarm system.
   

the only alarm that "sounds" when installing a new battery is an aftermarket alarm and the only way to resolve it will be if you have the remotes for the vehicle

search under the dash for a little black box
it should look like is was installed with zip ties

simply unplug it and your good to go

If you car has an alarm try depressing the Valet switch and de-activate the alarm. What happens with car alarms is they are auto activated when the battery is dead and re-connected. Also go to the starter itself and find the solenoid. There are usually one or 2 single wires attached to the rear of the soleniod. One is an ignition bypass and the other is 12VDC from the start switch. Have someone turn the key and check for 12VDC on the wires. Only one of them will have voltrage when the key is turned to start. If you have 12DC on the wire terminal with the key turned to start then you have a bad starter / start soleniod.

by using vasoline or even grease, apply around battery terminals to prevent corrosion.

If your alarm system is an aftermarket system..it will have a valay switch to diss arm..it is usualy a small talgo switch located under the dash near the drives feet..if so just flick it off and install your new battery..then flick it back on when done...IF tour allarm is a factory one you must incert the key and turn to start passition..this should reset your sytem...