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Transfer Case Shift Control Switch Inoperative

Transfer Case Shift Control Switch Inoperative

Circuit Description
The range/mode switch circuit consists of the following 5 switches:
^ 4HI
^ AUTO 4WD
^ 2HI
^ 4LO
^ Neutral

The transfer case shift control module supplies a regulated 5 volts, DC to the switch through the 5-volt regulator circuit. The current travel through the resistor of the currently active switch. The switch then returns current to the transfer case shift control module through the switch signal circuit.

The transfer case shift control module constantly monitors this signal voltage to determine the condition of the mode switch circuit.

When each switch is depressed, the switch will complete a circuit through the respective resistor. The transfer case shift control module continuously monitors the switch input to determine which of the following buttons were selected by the driver:
^ 4HI
^ AUTO 4WD
^ 2HI
^ 4LO

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. Tests the functionality of the mode switch.
3. Tests the modules ability to operate the transfer case modes.

Transfer Case Shift Control Switch Inoperative (1 Of 2):




Transfer Case Shift Control Switch Inoperative (2 Of 2):