power locks (searched and no help)

[WILDACEX187]

well its time to put an alarm on my car but i gotta get the power door locks to work right. usually when u're inside the car and u lock the driver door the passenger should lock, same thing if u unlock it. well when i do this in my car all i hear on the passenger side is a click but the lock doesnt move. BUT if i unlock the car with the key from the passenger side (driver side only opens driver side not both ) it opens both

how do i get it to open both when i unlock the driver side door and when i lock the driver side door? all i hear is a click inside the passenger door when i try it. thanx for any help that u guys can give me