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

Transfer Case Shift Control Module


Object Number: 203290  Size: LF
(1)Right Side Cowl Panel
(2)Transfer Case Shift Control Module Connector (Not Used on Selectable)
(3)Transfer Case Shift Control Module Connector
(4)Transfer Case Shift Control Module
Figure 2:

Transfer Case (NP4)


Object Number: 357141  Size: LF
(1)C116
(2)Transfer Case Encoder Motor
(3)Vehicle Speed Sensor (VSS) and Connector
(4)Propshaft Speed Sensor - Rear and Connector
(5)S134
(6)Propshaft Speed Sensor - Front and Connector
Figure 3:

Transfer Case, RH Rear (Bravada)


Object Number: 421497  Size: LF
(1)Propshaft Speed Sensor - Rear and Connector
(2)Active Transfer Case Harness
(3)Transfer Case Encoder Motor and Connector
(4)Transfer Case (NP4)