Resetting the Power Tailgate Control Unit
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2017 Honda Odyssey, 2016 Honda Odyssey, 2015 Honda Odyssey, 2014 Honda Odyssey, and 2013 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
If the battery terminal is disconnected or the No. B16 (10 A) fuse in the under-hood fuse/relay box is removed while the power tailgate is operating, the power tailgate will not be able to open or close automatically until it is reset. To reset the system, fully close the tailgate manually. Once the battery terminals are reconnected or the No. B16 (10 A) fuse in the under-hood fuse/relay box is replaced, the power tailgate system automatically resets. Make sure the power tailgate operates properly.