Circuit/System Description
WARNING: This page is about a different car, the 2016 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.
The body control module applies battery positive voltage to the rear compartment lid unlatch relay control circuit which energizes the coil side of the relay. The switch side of the relay then closes, supplying battery positive voltage to the control circuit of the rear compartment lid latch. The rear compartment lid latch then releases the rear compartment lid so that it may be manually raised to an open position.