See also:

Programming HomeLink
NOTE Some vehicles may require the ignition switch to be turned on or to the second (“accessories”) position for programming and/or operation of HomeLink. It is also recommended that a new ba ...

Replacing the battery
1. Switch off the ignition. 2. Wait at least 5 minutes after switching off the ignition before disconnecting the battery so that all information in the vehicle's electrical system can be stored ...

Limitations
Even if a fairly small section of the screen image appears to be obstructed, this may mean that a relatively large area behind the vehicle is hidden and objects there may not be detected until the ...