Circuit Description

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The transfer case encoder is a switch that converts a shaft position, representing a mode or range position, into electrical signals for use by the transfer case shift control module. The encoder houses 4 Hall effect sensors that are used for channels P, A, B, and C. These sensors provide a path to ground, when a magnet, (part of the Motor Encoder), passes over them.

The transfer case shift control module supplies an 8 V reference and a ground circuit for the encoder Hall effect sensors to function.

The transfer case shift control module supplies current limited 5 V on all the channels, thus as these channels are pulled to ground, the module can interpret the location of the transfer case shift position.

This DTC detects that the transfer case is unable to successfully complete a shift to a requested mode or range.