Hello. I removed the rear left inner lining to get the engine and mechanics of the tailgate motorization.When the door is open and I press the remote control, only the turn signal flashes. No motor noise, no beeps etc.If the door is closed, it flashes and beeps after press remote control. When you sit inside, you can see how the gears interlock.After that, the gears go apart again. What should I examine, or what is usually broken? Thanks, Tobias Claren