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

Low Speed GMLAN


Object Number: 1884068  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN (4.3L/4.8L/5.3L/6.0L)
Figure 2:

High Speed GMLAN 4.3L/4.8L/5.3L/6.0L


Object Number: 1884072  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN (6.6L)
Low Speed GMLAN
Figure 3:

High Speed GMLAN 6.6L


Object Number: 1925728  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN (4.3L/4.8L/5.3L/6.0L)