Greetings and Welcome to Just answer.
I will do my best to assist you. When you are finished please click on accept only if you are satisfied. I don't get paid unless you do.Please do not accept if you cannot leave positive feedback. I don't know if you are a tech or a just working on your own vehicle so we may have to fine tune the answer. I only know as much about your problem as you have told me in your post, so my answers will be based on what you tell me so please add all the details you can.
There is not a manual close function on this system so we need to get the motor working.
When it stops at half way, can you reverse it to open and does it work?
OK, this sounds a motor and possible a cable issue. If the motor stopped and that was it, then I would say only motor. With it reversing, that sounds like the cables are involved as well. These work with a cable that has teeth on each side, and these interact with the teeth of the motor to move.
The second possible issue is the limit switches in the motor assembly that tell it when the glass is in a certain position. If those fail, it will react in this manner.
I know you don't want to hear this, but no manual way to close that is easy. YOu can take the headliner down to get at the motor and you could try turning the motor manually or tapping in it to reset the switch if there is debris caught in there.
Not likely. If it only needs the motor they will only replace the motor.
I would have them double check what we discussed and make sure they are not going to try the whole thing.
Tape on the harness is normal.
Moving the wires suggests there may be a poor connection at the terminals. If that is the case, those terminals can be replaced. I would try it out like this to confirm. Try moving the wires in different ways.
IF that remains constant, then replace the terminals.