GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2009 🢒 Lucerne 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Door Control Module Schematics
Figure 1:

Driver Door Module (DDM)
Object Number: 2081882 Size: FS
Figure 2:

Front Passenger Door Module (FPDM)
Object Number: 2081885 Size: FS