Electronic Shift Transfer Case: Notes

The New Venture Gear NV 273 electronic shift transfer case is a 3-piece aluminum design. The unit transfers engine power from the transmission to the front and rear axles. Under normal driving conditions the unit is in 2WD  , but when desired, the operator may shift into 4X4 High or 4X4 Low. The transfer case is shifted electronically. The unit is lubricated by a positive displacement fluid pump that channels fluid flow through holes in the mainshaft.

The encoder assembly used for mode indication is of a Hall-effect type. The system uses a total of 4 independent transistors for mode recognition. Each transistor is associated with a specific range of motor movement. When the circuit to each transistor is closed, a ground path to any of the -A-, B-, C- or D- encoder pins is accomplished. When the circuit to each transistor is open, the connection to any of the -A-, B-, C- or D- encoder pins is pulled to voltage. Mode indication is "decoded" by the 4X4 control module based on the varying combinations of signals coming from the transistors.