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

DLC Power, Ground, and Low Speed GMLAN


Object Number: 1558372  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
High Speed GMLAN
Underhood Fuse Block - B+ Bus
Underhood Fuse Block - RUN / CRANK Relay, I/P IGNITION, PRK / NEUT, BCK UP / HTD SEAT, ABS (10A), ECM TRANS, LTR, ABS (30A), EPS, BCM 2, BCM 3, and S-BAND ONSTAR Fuses
Computer/Integrating Systems Schematic Icons
G201 and G203
G201 and G203
Figure 2:

High Speed GMLAN


Object Number: 1558373  Size: FS
Master Electrical Component List
Data Link Communications Description and Operation
Control Module References
DLC Power Ground, and Low Speed GMLAN
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons
Computer/Integrating Systems Schematic Icons