GM Service Manual Online
For 1990-2009 cars only

Reference on Schematic

Section Number - Subsection Name

Data Link Connector (DLC) - Cell 50

8 - Data Link Communication

Ground Distribution - Cell 14

8 - Wiring Systems

Instrument Cluster - Cell 81

8 - Instrument Panel, Gauges and Console

Power Distribution - Cell 10

8 - Wiring Systems

Powertrain Control Module - Cell 20

6 - Engine Control Systems