I have a 1998 Dodge Durango and when I turn my headlights on the AC shuts off and and when the door opens the AC shuts off. Also, my power locks click but do not lock or unlock. What could this be?

SOURCE: 2001 Dodge Durango Power Lock Problem

Is this your problem?
http://dodgeram.info/tsb/2003/08-023-03.htm

SOURCE: 1999 DODGE DURANGO AUTOMATIC DOOR LOCKS.

That feature is called rolling locks.
In order to program the rolling door locks you will need to do the following procedure (listed on page 10 of the owners manual).
1. Close all of the doors.
2. Place the key in the ignition and cycle the key from the OFF to the ON position for a total of 4 to 5 times, ending in the ON position, do not start the engine.
3. Press the driver's side power lock switch to LOCK the doors within 30 seconds of cycling the key.
4. You will hear a single chime when programming is complete.
5. To cycle the feature on/off repeat the procedure.

SOURCE: 1998 Toyota Avalon with power door locks, front

Check this site out
you need the passenger side door lock assembly kit.
There is one posted for sale in the US on this site. just scroll down for the following information and link
Used 1998 Toyota Avalon passenger door lock assembly 1998 Toyota Avalon
passenger door lock assembly
this is the part that surrounds the lock driver side. Car color is green cary, North Carolina 27513
The solenoid or actuator arm for the door lock assembly is probably not working to full spec.

Hope this helps.

SOURCE: 2004 Dodge Ram 1500 Quad Cab Drivers side power door lock broken

Sounds like the link rod to the latch are jammed in the locked position by something inside the door or it came off. Any way, you have to remove the door panel to get access to it.

SOURCE: the power door locks will unlock only, not lock.

I am looking for the same problem. The power door lock work only on to unlock. When I try to lock the doors I hear only a cliking three time but the doors doesn't unlock