I just bought a 1998 Nissan Altima GXE. You should be able to turn the key in the door lock one direction to lock all the doors. If you turn it once in the other direction that one door unlocks. If you turn it twice in that direction, all doors unlock. The problem is that on my car the only thing that works is turning the key twice to unlock. Turning it once in the lock position WILL NOT lock the doors. Turning it once in the other direction WILL NOT unlock that door. The driver's door and passenger door are both working & not working identically. Can the problem be a fuse? If so, which one? None of the fuses are labelled "power locks." Is the problem the door lock module? Thank you!