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

Cell 138: Brake Transaxle Shift Interlock (BTSI)


Object Number: 255268  Size: FS
Tilt Wheel/Column Components
Automatic Transmission Shift Lock Control Description
Cell 138: Park Neutral Position Switch
Data Link Connector Schematics
Ground Distribution Schematics
Handling ESD Sensitive Parts Notice
Figure 2:

Cell 138: Park Neutral Position Switch


Object Number: 255273  Size: FS
Tilt Wheel/Column Components
Automatic Transmission Shift Lock Control Description
Cell 138: Brake Transaxle Shift Interlock (BTSI)
Data Link Connector Schematics
Ground Distribution Schematics
Handling ESD Sensitive Parts Notice
Powertrain Control Module Connector End Views