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

Vehicle Theft Deterrent (VTD) System


Object Number: 885781  Size: FS
Theft Systems Description and Operation
Battery Voltage to the Rear Fuse Block
IGN SW, PRK/REV Fuses and the PARK and REVERSE Relays (Fuse Block Rear)
Battery Feed to the Fuse Block Underhood
ABS, PCM BATT Fuses and the Cool Fan 1 Relay (Fuse Block Underhood)
Ignition Switch Positions
Ignition Switch Positions
G201 (2 of 2)
G201 (2 of 2)
Serial Data Class 2
Master Electrical Component List
Content Theft Deterrent (CTD) System
Figure 2:

Content Theft Deterrent (CTD) System


Object Number: 765679  Size: FS
Content Theft Deterrent (CTD) Description and Operation
Serial Data Class 2
Master Electrical Component List
VTD and CTD Indicators
Vehicle Theft Deterrent (VTD) System
Horn Schematic
Low Beam Headlamps
Figure 3:

Indicators - VTD and CTD


Object Number: 765682  Size: FS
Theft Systems Description and Operation
Serial Data Class 2
G201 (1 of 2)
G201 (1 of 2)
Master Electrical Component List
Content Theft Deterrent (CTD) System