Circuit Description
WARNING: This page is about a different car, the 2004 GMC Sierra and 2004 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The transfer case shift control module senses rear slip. After several attempts of applying torque to the front wheels, by activating the encoder motor, the transfer case still sees a difference in speed between the front propshaft speed sensor and rear propshaft speed sensor.