Transfer Case Range Select Switch Input (2WD, 4WD Auto, 4WD Lock, And 4WD Low Select Switch)

The transfer case range select switch is hardwired directly to the Instrument Panel Cluster (IPC). The switch position is read by the IPC and is communicated to the Body Control Module (BCM) via the CAN-B bus. The BCM then rebroadcasts this information onto the CAN-C bus where the Drivetrain Control Module (DTCM) is a receiver.

IPC will support circuitry which interfaces to the system's Transfer Case Range Select Switch, including a Transfer Case Range Select Switch voltage supply and a Transfer Case Range Select Switch input. The purpose of this circuitry is to determine the mode currently being requested by the operator via the resistance ladder network in the shifter assembly, where the Transfer Case Range Select Switch is packaged.

The NEUTRAL Select Switch Input will provide the operator with the ability to place the Transfer Case in Neutral. The Transfer Case Range Switch input will provide the operator with the ability to place the transfer case in 2WD, 4WD AUTO, 4WD LOCK, and 4WD LOW. The NEUTRAL Select Switch is a momentary pushpin switch; the Transfer Case Range Select Switch is a 4-position rotary contact switch; both of these switches are provided through a resistor network for diagnostic purposes. The input will have an internal 1.0K +/- 1% pull-up resistor to 5V.

As the selected position in the switch varies and/or the NEUTRAL Switch is depressed or not, the resistance between the IPC voltage supply and Transfer Case Range Select Switches input will vary. Hardware, software, and calibrations within the Cluster will be provided that interpret the external resistance between the module's Transfer Case Range Select Switches voltage supply and Transfer Case Range Select Switches inputs as given in the table below: