OPERATION
As the position of the selector switch varies, the resistance between the Mode Sensor supply voltage pin and the Mode
Sensor output will vary. Hardware, software, and calibrations within the Front Control Module (FCM) are provided that
interpret the selector switch resistance as given in the table below: SELECTOR SWITCH INTERPRETATION
SELECTOR SWITCH INTERPRETATION
Required Interpretation
Resistance Range (ohms)
Shorted
<150
AWD+NEUTRAL
176-200
4LOCK+NEUTRAL
190-216
4LO+NEUTRAL
199-226
AWD (Default)
1159-1287
4LOCK
2259-2503
4LO
4820-5334
Open/Diagnostic
>19K
The internal structure and function of the selector switch is such that the connection is made to the Open/Diagnostic
resistor before the connection to the individual position resistors is broken. Because of this characteristic, if the
resistance between the Mode Sensor supply voltage pin and the Mode Sensor output pin is >19k ohms, the position
resistor is open.
ASSEMBLY-SHIFT MOTOR/MODE SENSOR
DESCRIPTION
The shift motor (1) is an electromechanical device
consisting of a DC permanent magnet motor, gear
train, and an analog position sensor. The shift motors’
overall function is to move and lock a gear that moves
the mode and range forks found in the transfer case.
This allows the transfer case to be shifted electrically
to multiple operating positions (4LOCK, AWD, N (neu-
tral), and 4LO). The operating current of the shift
motor under stall conditions is 30 amps maximum at
72° F with 13.5 volts, at the motor leads.
OPERATION
Shifting in the transfer case occurs when a Pulse Width Modulated (PWM) voltage is supplied to the shift motor by
the Front Control Module (FCM). A linear analog position sensor located inside the shift motor, provides the FCM
with the motors’ angular, rotational position. With this information, the FCM continuously knows the motors’ position,
and therefore allows it to accurately control the motors’ operation, including voltage polarity which is used to control
motor direction.
HB
TRANSFER CASE - NV244 GENII - SERVICE INFORMATION
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