GM Service Manual Online
For 1990-2009 cars only
Makes šŸ¢’ GMC_Truck šŸ¢’ 2001 šŸ¢’ Yukon - 4WD šŸ¢’ Body and Accessories šŸ¢’ Cellular Communication šŸ¢’ Cellular Communication Component Views
Figure 1:

OnStarĀ® Subsystem Components (Utility)
Object Number: 623162 Size: MF
(1)Cellular Antenna
(2)Cellular Telephone Microphone
(3)Global Positioning System (GPS)
(4)Junction Block-Body
(5)Vehicle Communication Unit
(6)OnStarĀ® Button Assembly
(7)Vehicle Interface Unit
Figure 2:

Behind the Upper Right Side of the I/P Components
Object Number: 623205 Size: MF
(1)Vehicle Interface Unit (VIU)
(2)VIU Connector C-2 (Blue)
(3)VIU Connector C-1 (Red)
(4)I/P Panel-RH
Figure 3:

Onstar Vehicle Communication Unit (VCU)
Object Number: 623169 Size: MF
(1)IP Support Bracket
(2)Vehicle Communication Unit (VCU)
(3)Vehicle Communication Unit (VCU) Connector
(4)C248
(5)Vehicle Communication Unit (VCU) Harness
Figure 4:

Roof Harness (w/OnStarĀ®)
Object Number: 623207 Size: MF
(1)Global Positioning System (GPS) Harness
(2)GPS Connector
(3)GPS Antenna
Figure 5:

Overhead Console -- OnStarĀ® Components
Object Number: 623185 Size: MF
(1)Inline Connector C211
(2)Overhead Reading Lamps
(3)OnStarĀ® Microphone
Figure 6:

Center of the I/P -- OnStarĀ® Components
Object Number: 623182 Size: MF
(1)OnStarĀ® Button Assembly Connector
(2)OnStarĀ® Button Assembly
Figure 7:

Behind the Center of the I/P -- Radio Connections
Object Number: 623166 Size: MF
(1)Radio
(2)I/P Connector to Radio Connector C-3
(3)Jumper Connector, With Remote CD