GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 Sierra Classic - 4WD 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Hydraulic Brake Schematics
Figure 1:

Power, Ground, Serial Data, Indicator Control, and Switches
Object Number: 1775062 Size: FS
Master Electrical Component List
Brake Warning System Description and Operation
Control Module References
Supplemental Brake Assist
Power, Ground, DLC and Splice Pack SP205
G104, G107, and G110
Figure 2:

Supplemental Brake Assist
Object Number: 1775065 Size: FS
Master Electrical Component List
Brake Assist System Description and Operation (Vacuum Assist)
Control Module References
Power, Ground, Serial Data, Indicator Control, and Switches
Ignition Switch - ACC/RUN and RUN/START BUS BARS and IGN B Fuse
G104, G107, and G110
B+ Bus Bar
ETC/ECM, INJ1, INJ2, PCM 1, and SBA Fuses - Gas
ETC/ECM, INJ1, INJ2, PCM 1, and SBA Fuses - Gas
Gages, Vehicle Speed Sensor, Engine Oil Pressure, and Fuel Level Sensors
G104, G107, and G110
G203 - 1 of 2
G115 and G200 - 1 of 2