GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 Sierra - 4WD 🢒 Power and Signal Distribution 🢒 Data Communications 🢒 HVAC Schematics
Figure 1:

Module Power, Ground, Serial Data and Blower Controls
Object Number: 2064927 Size: FS
Figure 2:

Mode and Temperature Controls
Object Number: 2064929 Size: FS
Figure 3:

A/C Compressor Controls (C67)
Object Number: 2064933 Size: FS