I have the following problem. The power liftgate works fine for a couple of days, and it will not work by pressing the key or button under the wheel. In order to open, I press the button on the liftgate and opens. I can only close it by pressing the key on the liftgate but it doesn't close all the way, and I have to push it with my hands. Then it will work fine for a couple of days and then the same thing happens again. Any suggestions?