Reference Information

Schematic Reference

• OnStar/Telematics Wiring Schematics 
• Radio/Navigation System Wiring Schematics (IOS/IOU) , or Radio/Navigation System Wiring Schematics (IOR) 

Connector End View Reference

Master Electrical Component List , or Component Connector End Views - Index

Description and Operation

• OnStar Description and Operation (without IOU/IOT/IOR) , or OnStar Description and Operation (IOU/IOT/IOR) 
• Radio/Audio System Description and Operation (IOS/IOT/IOU) , or Radio/Audio System Description and Operation (IOR) 

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-49903  OnStar^® Antenna Diagnostic Tool Kit