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

OnStar - UE1


Object Number: 1794989  Size: FS
Master Electrical Component List
OnStar Description and Operation
Control Module References
Data Link Communication
Entertainment/Communication Schematic Icons
Entertainment/Communication Schematic Icons
Entertainment/Communication Schematic Icons
Rear Fuse Block B+
G402
Power, Ground, and Low Speed GMLAN
G305
Figure 2:

Data Link Communication


Object Number: 1794997  Size: FS
Master Electrical Component List
OnStar Description and Operation
Control Module References
UE1
Power, Ground, and Low Speed GMLAN
High Speed Serial Data