1998 SSANGYONG MUSSO clutch

5D2-4 TRANSFER CASE (TOD)
FUNCTION DESCRIPTION
lTOD System Select Mode (4H and 4L)
4H is the mode when drive normally of which gear ratio is 1:1 and 4L mode distributes power to front and rear
wheels 50:50 of which gear ratio is 2.48:1.
lTOD System Function (select 4H mode)
TOD system controls clutch mechanism to comply with rotation in front and rear propeller shaft and if its difference
exceeds the permissible range, corresponding power is distributed into front wheel through EMC (Electro-Magnetic
Clutch).
Hall effect sensor signals speed on front and rear propeller shafts going through with TOD control unit.
Transfercase clutch coil is activated by variable current on exceeding difference of speed in front and rear propeller
shafts.
lFunction of 4L Mode
When select 4L mode, EMC is locked to apply maximum torque into front and rear propeller shafts. Shift motor
rotates also 4L position by rotation of cam thus propeller shaft torque changes from 1:1 to 2.48:1 by planetary
gear set.
lShift Motor
It locates backside transfer case, which drives rotary helical cam.
When mode select switch changes to 4L, shift fork is on position for 2.48:1 by rotation of helical cam.
lTransfer Case
TOD transfer case distributes power into front and rear axle by operation of 4H/4L switch and shift motor.
Shifting 4H to 4L, is performed towards reducing HI-LO collar by means for connection HI-LO shift fork with
output shaft in order to join with planetary gear. Torque transmits input shaft then sun gear rotating front planetary
gear. Front planetary gear join with output shaft and drives LO position.

TRANSFER CASE (TOD) 5D2-5
Definitions
Rear Speed Sensor A Hall Effect speed sensor which produces a square wave. 0-5Vdc signal in
response to a rotating 30 tooth wheel coupled to the rear propshaft inside the
Transfer Case. Each rotation of the rear propshaft will result in 30 speed sensor
pulse.
Front Speed SensorA Hall Effect speed sensor which produces a square wave. 0-5Vdc signal in
response to a rotating 30 tooth wheel coupled to the front propshaft inside the
Transfer Case. Each rotation of the front propshaft will result in 30 speed sensor
pulse.
EMC An Electromagnetic clutch used to control the amount of torque applied to the
front propshaft.
TOD
TMTorque on DemandTM.
Duty Cycle Duty Cycle is the time the EMC is on divided by the period in which it is being
modulated.
Touch-off A minimum amount of duty cycle applied to the EMC.
Front OverrunA condition where the front propshaft is turning at a rate which is faster than the
rear propshaft.
Rear Overrun A condition where the rear propshaft is turning at a rate which is faster than the
front propshaft.
High RangeThe highest (numerically lowest = 1 :1) gear ratio between the input and outputs
of the Transfer Case.
Low RangeThe lowest (numerically highest = 2.48:1) gear ratio between the input and outputs
of the Transfer Case.
4H/4L Switch A switch which selects the desired gear ratio.
Shift Motor Electric motor which changes the Transfer Case range.
Position Encoder A set of 4 Gray code switches which provide feedback to the TCCU indicating the
position of the Shift Motor.
Clutch Interlock Switch A switch on vehicles equipped with a manual transmission which indicates that
the clutch pedal is depressed.
Neutral Safety Switch A switch on vehicles equipped with an automatic transmission which indicates
that the transmission is in neutral.
Shift Inhibit Speed The vehicle speed above which Transfer Case shifts are disallowed. Vehicle speed
is indicated by propshaft speed measurement.

TRANSFER CASE (TOD) 5D2-13
Speed Sensor/Clutch Coil and Motor Connector
Speed senso /clutch coil and shift motor connector locate upper
backside transfer case (upper part of shift motor).
- Shift motor connector : Black
- Speed sensor and clutch coil connector : White
Shift Mtor Connector Speed Sensor/Clutch Coil Connector
Rear View for Connector
Pin
A
B
C
D
E
F
GFunction
Position 4
Motor (Counter-Clockwise)
Position 3
Position 2
Position 1
Position Retum
Motor (Clockwise)Pin
H
I
J
K
L
M
NFunction
Clutch Coil (EMC)
Front Speed Return
Front Speed
Front Speed Sensor Supply
Rear Speed Sensor Supply
Rear Speed
Rear Speed Return Rear View for Connector

TRANSFER CASE (TOD) 5D2-25
Error in electro - magnetic clutch : fault code
“1721”, “1722”
lPhenomenon
1. Upon diagnosis by SCAN-100, it displays on fault
codes “1721,1722”.
lCause
1. Defect in electro - magnetic clutch
2. Defect in connector or wiring
- Open or short from EMC to the supply : 1721
- Short EMC to ground : 1722
Ye s
No
C1
Ye s
No Ye s
No
11-15Vdc
Ye s
No
C2
Ye s
No
Test Stage / ContentsResult
Stage Test Contents and ProcedureSpecified Value
/Yes/NoCountermeasure
Check relevant connector connection status.
1. Check relevant connector connection status with TOD
control unit.
- Does it connect correctly ?
2. Check connection status of speed sensor and clutch
coil connector (7 pin) in transfer case.
- Does it connect correctly ?
3. In case of bad connection, connect it correctly then
perform the follows :
a. Delete the memorized fault code in control unit with
Scan - 100.
b. Ignition “OFF”.
c. Ignition “ON”.
d. Diagnose by SCAN-100
- Does it display on fault codes “1721,1722” ?
Check supply voltage into electro-magnetic clutch.
1. Ignition “ON”
2. Measure voltage between pin 4/19(+) and 17/18(-) in
TOD control unit connector.
- Specified value
- Measured value is within specified range ?
3. If the specified value would not be measured, perform
the follows :
a. Check battery voltage (charging condition)
b. Check open circuit on No.13 fuse (20A)
c. Check relevant wires.
- Is the above 3a, 3b, 3c normal ?Perform C1-2 stage
Perform C1-3 stage
Perform C2 stage
Normal system Perform C2 stage
Perform C1-3 stage
Perform C3 stage
Perform C2-3 stage
Perform C3 stage
lCharging/
Replace battery
lReplace fuse
lRepair wires

5D2-26 TRANSFER CASE (TOD)
0Vdc
11 - 15Vdc
Ye s
No
2.5W
Ye s
No C3Test Stage / Contents
Result
Stage Test Contents and ProcedureSpecified Value
/Yes/NoCountermeasure
Check resistance of electro-magnetic clutch.
1. Disconnect 30 pin connector from TOD control unit.
2. Measure resistance between pin 3 and 7 in wiring
connector using multi-tester.
- Specified value
- Measured value is within specified range?Perform C4 stage
l0W : short
l¥W : open
C4Check operational voltage of elector-magnetic clutch.
1. Ignition "ON"
2. Measure voltge between pin 3(+) and 17(-)in TOD
control unit connector.
- Specified value 4WD high
4WD low
- Measure value is within specified range ?Replace TOD
control unit
Replace wire

TRANSFER CASE (TOD) 5D2-27
Defect in speed sensor : fault code 1731, 1732,
1733, 1734, 1735,1736
lPhenomenon
1. Upon diagnosis by SCANNER, it displays on fault code
1731, 1732, 1733, 1734, 1735 and 1736.
2. “4WD CHECK” lamp illuminates continuously when
ignition “ON”.
lCause
1. Defect of speed sensor (front, rear).
2. Defect of power supply.
4.75-5.25Vdc
Ye s
No D1
Ye s
No
D2
Ye s
Ye s
Ye s
No D3Test Stage / Contents
Result
Stage Test Contents and ProcedureSpecified Value
/Yes/NoCountermeasure
Check power supply of speed sensor.
1. Ignition “ON” or driving mode
2. Measure supply voltage between pin 16 (+) and 13 (-) in
TOD control unit connector using digital multi-tester.
- Specified value
- Measured value is within specified range ?
Check connection status of connector.
1. Check connection status of speed sensor/clutch coil
connector and TOD control unit connector.
- Does it connect correctly ?
2. In case of bad connection, connect it correctly then
perform the follows:
a. Delete the memorized fault code in control unit by
SCANNER.
b. Ignition “OFF”.
c. Ignition “ON”.
d. Diagnose by SCANNER.
- It does not display fault code.
- It displays one or more fault code among 1731 to
1736.
Check output wave of front and rear speed sensor.
1. Upon driving mode.
2. Check output wave of each speed sensor by SCANNER.
3. Is it normal on output wave ?Perform D3 stage
Perform D2 stage
Perform D3 stage
Perform D2-2 stage
Normal system
Perform D3 stage
Perform D4 stage
Replace speed
sensor then
perform D2-2 stage

TRANSFER CASE (TOD) 5D2-35
Removal & Installation Procedure
1. Disconnect (-) cable from battery.
2. Lift on vehicle and make sure on safety.
Notice
Be careful for catalytic converter due to high temperature
after driving or engine running.
3. Prepare a vessel to drain transfer case and manual
transmission oil.
4. Release drain plug and drain transfer case and manual
transmission oil.
If planar damper is installed, unscrew 4 bolts and remove
the planar damper.
Notice
Oil drain should be along with whole transfer case
disassembly and assembly.
5. Disconnect transmission extension wiring connector back
side transfer case.
Notice
When disconnect connector, make sure on direction of
locking tab towards inside.
6. Disconnect shift motor/clutch coil connect (Black 7 pin)
connector upper backside.
7. Disconnect front and rear speed sensor connector (white
7 pin).
8. Disconnect speedometer sensor connector right upper
side.
9. Disconnect breather tube front upper side transfer case
(upper connecting point of transfer case and front
propeller).
10. Prepare hydraulic jack and support transfer case assembly.

TRANSFER CASE (TOD) 5D2-37
Replacement of Shift Motor
1. Disconnect (-) cable from battery.
2. Disconnect shift motor/clutch coil connector (black pin7)
upper backside.
3. Unscrew 3 units of shift motor mounting bolts (M10).
4. Unscrew 1unit of bracket mounting bolt (M10).
Installation Notice
Tightening Torque 9 - 11 Nm
Notice
When disconnecting shift motor and mounting bracket, it is
required to unscrew 2 units of adjusting bolts (M10) form
motor and bracket.
5. Keep shift motor even then pull rearward.
6. Clean connection surface of transfer case and shift motor.
7. If necessary, make a test by SCANNER with shift motor
assembly.
Notice
Do not disassemble shift motor. If necessary, replace by
shift motor assembly unit.
8. Applying sealant into connecting surface for new shift motor.
9. Installation should follow the removal procedure in the
reverse order. Before installation, make sure that motor
position match with mode of 4H/4L switch.
Reference
When accord position of motor with 4H/4L switch and transfer
case match position of the disconnected motor and new
one.