Exterior trunk button

As soon as the vehicle is unlocked, the trunk can be opened with the exterior trunk button in the trunk. The button switches to ground when the exterior trunk button is pressed.

The button is monitored by the junction box electronics. When the signal of the button changes to low, the trunk is unlocked and can be opened.

Fig 1: Identifying Exterior Trunk And Exterior Trunk Button

Courtesy of BMW OF NORTH AMERICA, INC.