Durango 4WD V8-4.7L VIN P Flex Fuel (2007)
Transfer Case Actuator: Description and Operation
NV144 Transfer Case
Description
DESCRIPTION
The shift motor (1) is an electromechanical device consisting of a DC permanent magnet motor, a motor brake, a gear train and an analog position
sensor. The shift motors' overall function is to move and lock a gear that moves the mode fork found in the transfer case. This allows the transfer case to
be shifted electrically to multiple operating positions (4LOCK and AWD). 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
OPERATION
Shifting in the transfer case occurs when the shift motor brake is released and 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.
