Circuit/System Description

The transfer case shift control module has 4 encoder channels coming out of it which are all supplied 5 volts. These 4 channels are P, C, A, and B, each running to a switch located inside the encoder/motor assembly. When a particular encoder channel is active, the switch is closed and 5 volts flows through the encoder signal return circuit. If the module wants to request motor position, a low side driver pulls the voltage low on the encoder signal return and the corresponding channel circuit indicating motor position.

The transfer case shift control module supplies 5 volts on all the channels. As these channels are pulled to ground, the module can interpret the location of the transfer case shift position.

This DTC detects a short to ground in the encoder signal return circuit, or a short to ground in the encoder channel circuits.