Power Transfer Case Actuator Motor
The power transfer case actuator motor consists of a permanent magnet DC motor that is mounted to the PTU extension housing. When commanded by the rear differential clutch control module, the motor, worm, and rotary cam all turn in one direction, not bi-directional. The linear cam pushed away from the rotary cam in the FWD position. When the rotary cam is rotated further, linear cam drops off the ramps allowing the shift collar to retract to AWD position. By rotating the rotary cam further, the ramps push the linear cam away back to the FWD position. Three ramps interface on the rotary/linear cams. One complete revolution of the rotary cam causes three shift engagements, to engage or dis-engage the rear propeller shaft and AWD mode. The actuator motor is controlled with a PWM signal from the control module. This circuit consists of a driver on both the Motor A and B circuits. The rotational position sensor is internal to the actuator motor assembly and is not serviced separately.