Lower the back door using either back door handle.
Make sure to push the back door down from the outside to close it.
The back door closing assist will activate and the back door will fully close automatically.

Canceling the power back door system (vehicles with a power back door)
Turn the main switch in the glove box off to disable the power back door system.

Power back door switch (vehicles with a power back door)
Adjusting the open position of the back door (vehicles with a
power back door)Park/neutral position switch ASSY (U241E/U140F)
REPLACEMENT
1. REMOVE ENGINE UNDER COVER NO.1
2. SEPARATE TRANSMISSION CONTROL CABLE ASSY
(a) Remove the nut from the control shaft lever.
(b) Disconnect the control cable from the control shaft lever.
(c) Remove the clip and disconnect the control cable from
the control cable bracket. ...