C0327
DTC C0327Circuit Description
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, which is part of the shift rail, passes over them.
The transfer case shift control module supplies a 8 V reference and a ground circuit for the encoder Hall effect sensors to function.
The transfer case shift control module supplies 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 an open, short to ground, or a short to voltage in the encoder feed circuit, an open in the signal ground circuit, an open, short to ground, or short to voltage in the Encoder channel circuits.
Conditions for Setting the DTC
The transfer case shift control module reads back all high or low voltage on the Encoder channel circuits.
Action Taken When the DTC Sets
^ All motor activity will stop and the Transfer Case Lock engaged.
^ A default rail to rail shift may be allowed, toggle between 4H and 2H.
^ The SERVICE 4WD indicator will be latched on for the remainder of the current ignition cycle.
Conditions for Clearing the DTC
^ The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists.
^ A history DTC will clear after 100 consecutive ignition cycles without a fault present.
^ History DTCs can be cleared using a scan tool.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. Determines if the transfer case control module is supplying the correct 8 V reference
3. Checks for proper voltage on the four encoder signal circuits.
4. Tests for an open or high resistance on the encoder signal ground circuit.
5. Tests the encoder signal circuits for an open, short to ground, or short to power.
6. Checks for a binding sector shaft.
7. Disassembly and overhaul for a binding sector shaft.