Opel Frontera UBS. Manual - part 1964

4B2–3

DRIVE LINE CONTROL SYSTEM (TOD)

condition, determines the optimum torque based on the
feedback control logic, and increases the torque to the
front wheels.
The control unit uses the signal from the throttle position
sensor to predict the future vehicle condition and the
intention of the driver with respect to acceleration and
deceleration, and determines the initial torque distribution
using these data and the information from the speed
sensors.
In case of small circle turning in the parking lot, for
example, the control unit minimizes the clutch pressing
force to restrict a braking phenomenon.  When the ABS
becomes active, the control unit optimizes the clutch
pressing force to ensure stable braking.

TOD Indicator Control

The TOD indicator on the instrument panel informs the
driver of the current working status of the transfer unit.
The information consists of two items: the drive mode
(2H, TOD, 4L, transition) and the torque split status of the
TOD (torque distribution level).  The indicator can display
occasional errors and corresponding error codes.

DRIVE LINE CONTROL SYSTEM (TOD)

4B2–4

System Components

Parts Location

A07RY00002

Legend

(1) T/F Connector
(2) 4H and 4L Switch
(3) High-Low Planetary Gear Set
(4) Mechanical Lock

(5) Multi Plate Disk Clutch Pack
(6) Electromagnetic Coil
(7) Rear Speed Sensor
(8) Front Speed Sensor

4B2–5

DRIVE LINE CONTROL SYSTEM (TOD)

Front and Rear Speed Sensors

The sensors are built in the transfer case, detect the
rotation of rotors directly coupled to the propeller shafts.
Thirty rectangular pulses are output per one rotation of
the propeller shaft.

261RW045

Electromagnetic Coil

Receives the duty signals from the TOD control unit and
controls the pressing force of the clutch pressure cam.

261RW044

Multi Plate Disk Clutch Pack

Transmits the torque determined by the clutch pressing
force to the front propeller shaft via the front drive chain.

262RW029

Mechanical Lock Sleeve

Couples the front and rear propeller shaft mechanically
when the transfer shaft is in the 4L position.

262RW028

DRIVE LINE CONTROL SYSTEM (TOD)

4B2–6

High-Low Planetary Gear Set

Establishes an auxiliary transmission mechanism.  When
the transfer shift lever is set to the 2H or TOD position, the
reduction gear ratio is 1.000 and the corresponding
driving force is generated.  When the transfer shift lever is
set to the 4L position, the reduction gear ratio is 2.480 and
the corresponding driving force is generated.

262RW030

4H and 4L Switch

Detects the shift position of the transfer from the
movement of the transfer lever and outputs signals to the
TOD control unit.

261RW002

Transfer Connector

Transmits the input and output signals of the speed
sensors, electromagnetic coil, and 4H and 4L switche to
the vehicle harness.  A waterproof 12-pin type is used.

261RW046

TOD Indicator Lamps (on the instrument
panel)

Inform the following items.

D

Bulb check

D

Drive mode

D

ABS IN status

D

BRAKE ON status

821RW049