Circuit/System Description

WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The transfer case encoder motor (TCEM) is a bi-directional, permanent magnet, DC motor. When energized, through motor control A or motor control B, the ground is provided by the opposing motor control circuit and then grounded through the transfer case shift control module (TCCM) ground circuit, the TCEM, through a series of gears, rotates the transfer case control actuator shaft which moves the transfer case two/four wheel drive actuator cam and transfer case high/low shift fork to shift the transfer case between the following modes or ranges:

2 HI
4WD HI
4WD LOW
Neutral

The transfer case control module monitors actuator current and incremental sensor output in order to shift the transfer case and verify that the proper position has been obtained. Deviations in current and position from expected values will cause this DTC to set.