OPERATION

During normal vehicle operation, the Final Drive Control Module (FDCM) monitors the mode sensor outputs at least every 2 milliseconds when the shift motor is stationary or active.

NOTE: All the parameter voltages referred to in the following information are calibrated items in the controller software and are subject to change.

NOTE: For a further explanation of Phase 1 through 3 shifting, (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSFER CASE CONTROL MODULE - OPERATION).

• 4LOCK TARGET REGION - The position shall be considered 4LOCK if the voltage is greater than or equal to encoder_4LOCK_min Volts and it is also less than or equal to encoder_4LOCK_max Volts.
• AWD TARGET REGION - The position shall be considered AWD if the voltage is greater than or equal to encoder_AWD_min Volts and it is also less than or equal to encoder_AWD_max Volts.
• AWD SHIFT LIMIT - During Phase 2 and Phase 3 shifting, shifts may become unidirectional when a voltage is greater than or equal to encoder_AWD_min Volts has been reached.

The mode sensor position will be considered invalid by the FDCM if the voltage is greater than or equal to encoder_High_Range_Limit Volts or if it is less than or equal to encoder_Low_Range_Limit Volts.

If FDCM looses the encoder signal during a shift, the FDCM will respond with a shift back in the opposite direction of travel to first attempt to find the encoder signal. If the signal is not found, the FDCM will drive motor in AWD direction for 1 second.

Refer to MODE SENSOR VOLTAGES table for the mode sensor voltages.

MODE SENSOR VOLTAGES