Lock Unit, Tailgate/Trunk Lid

Fig 1: Tailgate/Trunk Lid Lock Unit

Courtesy of VOLVO CARS OF NORTH AMERICA.

Applicable to the S80/S60: 

The lock unit in the trunk lid on the S80/S60 actually has no "unlocked" mode. The difference between locked and unlocked mode is whether or not the rear electronic module (REM) activates the lock unit when the switch in the trunk lid is pressed. Opening the trunk lid depends on whether central locking is in unlocked mode or not. There is a lock cylinder in the trunk lid as a mechanical reserve alternative. The lock cylinder is mechanically connected to the lock unit. The trunk lid can be opened via the lock cylinder with the key.

The switch on the trunk lid (S60/S80) and lock unit (3/78) are directly connected to the rear electronic module (REM).