Transfer Case: Description and Operation

MF1A TRANSFER / 4WD / AWD: ACTIVE TORQUE CONTROL 4WD SYSTEM: SYSTEM DIAGRAM

SYSTEM DIAGRAM





Communication Table






MF1A TRANSFER / 4WD / AWD: ACTIVE TORQUE CONTROL 4WD SYSTEM: SYSTEM DESCRIPTION

SYSTEM DESCRIPTION

1. FUNCTION OF MAIN COMPONENTS





2. OPERATION
(a) 2WD Mode
(1) The drive force is transmitted from the propeller shaft to the front housing.
(2) The AWD control ECU judges whether it is necessary to send drive torque to the rear wheels based on input from various sensors. When it is not necessary to send drive torque to the rear wheels, the electromagnetic solenoid is not operated.
(3) The drive force of the front housing is not transmitted to the shaft because the control clutch is not engaged.
(4) Accordingly, drive force from the propeller shaft is not transmitted to the rear wheels.





(b) AWD Mode
(1) The drive force is transmitted from the propeller shaft to the front housing.
(2) The AWD control ECU judges whether it is necessary to send drive torque to the rear wheels based on input from various sensors. When it is necessary to send drive torque to the rear wheels, the electromagnetic solenoid is operated.
(3) It attracts the armature to the control clutch side. This causes the control clutch to engage and the cam to rotate.
(4) The rotational movement of the cam causes the piston to push on the main clutch, causing the main clutch to engage.




(5) The amount of drive force that is transmitted to the rear wheels is controlled steplessly by controlling the amperage that is applied to the electromagnetic solenoid.
(6) Accordingly, drive force from the propeller shaft is transmitted to the rear wheels.