oil OPEL FRONTERA 1998 Workshop Manual

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–2
General Description
C07RW014–1
TOD (Torque on Demand) system is traction state control
system to vehicle.
Transfer Position and Drive Mode
Three drive modes can be selected through operation of
4WD AUTO switch and transfer lever.
Transfer Position
4WD AUTO SWModeDrive mode
HIGHON (NORMAL)2HRear wheel drive
OFF (PUSHED)TODElectronically controlled torque split
four wheel drive
4LON/OFF4LLow-speed mechanical lock-up four
wheel drive
The electronic control unit (ECU) judges the signals from
the transfer lever and 4WD AUTO switch, and controls
the transfer drive mode and shift-on-the-fly system
status.
TOD Control
The TOD position usually drives the rear wheels, and
transmits the torque to the front wheels with the help of
electronically controlled torque split mechanism
according to running conditions encountered. The driving
force is directly transmitted to the rear wheels. This force
is split by the transfer and delivered to the front wheels.
The magnitude of the torque transmitted to the front
wheels is controlled by changing the pressing force of the
multi plate disk clutch built in the transfer unit. Thepressing force of the clutch is controlled by changing the
duty cycle to the electromagnetic coil mounted to the rear
of the clutch. When the clutch is completely disengaged,
the rear wheels are driven. When the clutch is completely
engaged, a rigid four wheel drive mode is obtained. The
torque split status is controlled continuously between the
rear wheel and four wheel drive modes. This system
includes front and rear speed sensors, and receives
throttle position sensor information from ECM.
The control unit receives signals sent from these sensors
and changes the pressing force of the multi plate disk
clutch to determine the torque distribution on the front and
rear wheels. Therefore, when the slip of the rear wheels is
increased against the current torque level in the normal
rear wheel drive mode, the control unit detects the slip

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.
Bulb check
Drive mode
ABS IN status
BRAKE ON status
821RW049

4B2–43 DRIVE LINE CONTROL SYSTEM (TOD)
Diagnostic Trouble Codes
CodeTe c h 2 c o d e
(P code)ItemDiagnosisCheck flow No.
12—Start codeNormal—
13P1735RefShorted GND6
14P1731Front speed sensorInput abnormality (open, sig or com)2
15P1736RefShorted VB6
16P1737Front speed sensorInput abnormality3
21P1716TPSShorted or disconnected wiring, abnormality in
input7
23—ECUCPU abnormality1
24P1733Rear speed sensorInput abnormality (open, sig or com)5
25—CHECK lampShorted14
26—EMC (+)Shorted GND10
27P1738Rear speed sensorInput abnormality4
28P1760ADC (+) & AXLE SWOutput abnormality11
31P1721EMC (+)Shorted or disconnected coil/wiring9
32P1761ADC (+)Shorted or disconnected coil/wiring12
33P1762ADC (+)Shorted GND13
34—D-G MAPInput abnormality8
35—CHECK lampShorted or disconnected wiring14
36—ECUCPU abnormality1
37P1712ECUCPU abnormality1
38P1714ECUCPU abnormality1
TPS : Throttle Position Sensor
EMC : Electromagnetic coil
ADC : Shift on the fly (Axle Dis Connect)
D-G MAP : Discrimination engine type

4B2–59 DRIVE LINE CONTROL SYSTEM (TOD)
Check flowTrouble codePhenomenonStandard
931
(P1721)The electromagnetic coil is broken
or shorted to the battery or GND.—
D04RY00060

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–60
StepActionYe sNo
11. Clear the trouble code.
2. Start the engine
3. Set the TOD mode.
Is there DTC31 (P1721)?
Go to Step 2
Refer to “Trouble
intermittently
observed”.
21. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Is the continuity established between terminals (B–67)4 and
(B–67)12?
Go to Step 3Go to Step 5
31. Connect the ECU connector.
2. Start the engine.
3. Set the TOD mode.
Does the voltage between terminals 4 and 20 indicate at least
0.4V?
Go to Step 4Go to Step 6
4Is the battery voltage always observed between terminals 4 and
20?The harness is
short–circuited on
the battery.
Repair the circuit.
Go to
Step 8Go to Step 6
51. Disconnect the A–3 connector.
Is the continuity established between transfer connector
terminals (A–3)8 and (A–3)7?
The harness is
broken. Repair
the circuit.
Go to
Step 8
Replace the
transfer
electromagnetic
coil (solenoid
clutch).
Go to
Step 8
61. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Is the resistance between the connector (B–67) terminal 4 and 12
1.0
5.0?
The ECU has
failed. Replace
the ECU
Go to
Step 8Go to Step 7
7Is the resistance between the transfer connector (A–3) terminal 8
and 7 1.0
5.0?The harness is
disconnection or
short to GND.
Repair the circuit.
Go to
Step 8
Replace the
transfer
electromagnetic
coil (solenoid
clutch).
Go to
Step 8
81. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
“Diagnosis Flow”.
Return to Step 8

4B2–61 DRIVE LINE CONTROL SYSTEM (TOD)
Check flowTrouble codePhenomenonStandard
1026The electromagnetic coil is short-
circuited to GND.Resistance: 1.0 to 5.0 ohm (at
ordinary temperature)
D04RY00060

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–62
StepActionYe sNo
11. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Does the resistance between terminals (B–67)4 and (B–67)12?
indicate 1.0 to 5.0 ohm?
Go to Step 2Go to Step 3
21. Connect the ECU connector.
2. Start the engine.
3. Set the TOD mode.
When the throttle is operated between full close and full open
positions, does the voltage between terminals 4 and 20 indicate
0.1 to 1.0 V?The phenomenon
is not
reproduced.
Refer to
“Troubles
intermittently
observed”.
The ECU has
failed. Replace
the ECU.
Go to Step 4
3Does the resistance between transfer connector terminals (A–3)8
and (A–3)7 indicate 1.0 to 5.0ohm?
The harness is
broken. Repair
the circuit.
Go to Step 4
Replace the
transfer
electromagnetic
coil.
Go to Step 4
41. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
“Diagnosis Flow”.
Return to Step 4

4B2–71 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Does the resistance between terminals (B–67) 5 and (B–67) 11
meet the standard, 17 is not
reproduced.
Refer to
“Troubles
intermittently
observed”.
Go to Step 2
2Is the resistance between terminals (B–67) 5 and (B–67) 11 R<2
ohms?The signal line
circuit of the shift
on the fly system
is short-circuited
to GND. Repair
the circuit.
Go to Step 4
Go to Step 3
3Is the resistance between terminals (B–67) 5 and (B–67) 11 R=
9
7ohms?
The signal line
circuit of the shift
on the fly system
is layer
short-circuited*.
Replace the valve
(VSV).
Go to Step 4
Go to Step 4
41. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
“Diagnosis Flow”.
Return to Step 4
*Layer short-circuit : The coil is damaged by overcurrent.