05 Jetta Cooling Fans / Door Locks

We bought a used Jetta for my daughter in December. Around February, the "check engine" light came on. I took it to a Chief Auto Parts place where they read the code for me. It said that there was a problem with the cooling fans. They were not turning. It was cold so I was going to give it a couple of months to take care of it. Now, the light has gone out and one of the two fans works. The larger one works but the smaller one has not turned on. (that I know of)

My questions are, do the fans work independantly of each other? What makes the small one turn on? Does the car have to be in motion or extremely hot?

My second question is about the drivers door lock. When the car us unlocked (from the alarm mode)when you pull on the drivers door handle, nothing happens. The door does not open. The handle moves freely. If you pull the handle a second time, the door will open. What would cause this problem. The VW dealer wants over $100 just to look in the door. Is it something that can be fixed or does the lock actuator need to be replaced? By the way, when you hit unlock on the key, the actuator does make a click like it is unlocking the door.

Thanks