888 / 1906
TOD
8
MODE OF SHIFTS
A Momentary switch is used to provide two
different modes of operating positions as given
below:
4X2 Mode
Auto mode
The ECU will control mode shifts between 4X4
(AUTO)
and 4X2 by receiving a non-latching
mode switch request. When shifting between 4X2
to 4X4
(AUTO)
mode the ECU will utilize the TOD
clutch for synchronization of the front propeller
shaft and axle, and activate the front axle
disconnect unit to connect the front axle to the
driveline. The Front Axle Disconnect
(FAD)
feedback line is used to indicate the completion of
the shift. When shifting from 4X4
(AUTO)
to 4X2
the module will turn off the TOD clutch and
releases the front axle disconnect. The Front Axle
Disconnect
(FAD)
feedback line is used to
indicate the completion of the shift.
Shifts are only allowed when vehicle conditions
specified are satisfied. The shift conditions must
be met before the shift sequence can begin.
The shift conditions are as follows:
The battery voltage must be within the normal
operating range.
There is no active ABS/ESP event
No Active Clutch faults
No Active Front Axle Disconnect Faults
BENEFITS
Controlled distribution of torque to front and
rear axles.
Enhanced vehicle stability and handling
capability by interacting with ESP.
No need to drive the vehicle in reverse for
disengaging.
Improved fuel economy over full-time 4X4
(2%-4%).