GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Power, Ground, and Low Speed GMLAN Serial Data


Object Number: 2080053  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN Serial Data
Fuse Block - Underhood Bussing
HDLP MDL, DISPLAY, LT SPOT, and RT SPOT Fuses
Master Electrical Schematic Icons
Master Electrical Schematic Icons
G201
G202, and G204
Figure 2:

High Speed GMLAN Serial Data and Wake Up Signal


Object Number: 2080056  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
CAN Bus Serial Data - JL4
Power, Ground, and Low Speed GMLAN Serial Data
Figure 3:

CAN Bus Serial Data - JL4


Object Number: 2080060  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN Serial Data