WARNING: This page is about a different car, the 2008 Lincoln MKZ. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Audiophile Sound Radio Circuit, W/ SYNC (1 of 2)
Fig 2: Audiophile Sound Radio Circuit, W/ SYNC (2 of 2)
Fig 3: Audiophile Sound Radio Circuit, W/O SYNC (1 of 2)
Fig 4: Audiophile Sound Radio Circuit, W/O SYNC (2 of 2)