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SsangYong Stavic / SsangYong Rodius (2005 year). Manual - part 353

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

TOD

STAVIC - 2004.09

4H/4L Switch Input

Motor Position

Left stop

Left top

Top

Right top

Zone 1

Neutral

Zone 2

Bottom

Right stop

Left stop

Left top

Top

Right top

Zone 1

Neutral

Zone 2

Bottom

Right stop

Operation

Does not operate, 4L lamp off

- 4L lamp flickers

- Tries shifting to 4H if shifting conditions are satisfied.

- After shifting to 4H the flickering of 4L lamp stops.

Same as above

- 4L lamp flicker

- Tries shifting to 4L if shifting conditions are satisfied.

- After shifting to 4L the 4L lamp lights on.

Same as above

Does not operate, 4L lamp lights on

TCCU Initialization

• TCCU sends relevant data to meter cluster via CAN to diagnose and check the indicators when the ignition switch is

turned to ON. At this time, the 4WD indicators (4WD LOW, 4WD HIGH, 4WD CHECK) comes on for 0.6 seconds.

• If the selector switch position and the shift motor position code does not match when the IG power is turned ON, the

shift is controlled to move in the direction of the selector switch position

Interpretation of Position Sensor

- When the 4H/4L switch is operated and the position sensor recognizes the shift motor position while the system is

energized, the system operates as follows:

SYSTEM OPERATION

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

TOD

STAVIC - 2004.09

If 4H/4L switch position is not matched with shift motor position code with the ignition switch “ON”, the shift require-
ments operate to the direction of 4H/4L switch. However, the shifting requirements should be met to shift.

• Shifting requirements:

- The transmission is in neutral for 2 seconds after the shift is requested.

- Both propeller shaft speeds are below 43 Hz.

A command to shift will only be acted upon if the TOD is reading a valid code at the time the command to shift is made.

After a shift has started, the TOD will power the shift motor until the code for the requested position is read. If an invalid
code is read, the TOD will go into a default mode.

During a shift attempt, the shift motor will be energized for a maximum of 5 seconds.

In case of manual transmission, the clutch pedal should be depressed.

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

TOD

STAVIC - 2004.09

The electric shift system is responsible for changing the transfer case gear ratio by controlling the electric shift motor.

The TOD monitors the 4H/4L switch, neutral switch, speed sensors, position encoder, and ignition switch.

A range change is initiated when:

1. The 4H/4L switch is changed from 4H to 4L or from 4L to 4H.

2. The motor position (as indicated by the position encoder) does not match the 4H/4L switch immediately after the

ignition is turned on.

Shift Requirements

When a range change is initiated a diagnostic test will be completed on the motor, speed sensors, and position
encoder. If the diagnostic test fails, the shift will not be attempted. If all components are operating properly, the TOD will
attempt a range change after the following shift requirements are met:

1. The transmission is in neutral for 2 seconds after the shift is requested.

In case of manual transmission, the clutch pedal should be depressed.

2. Both propeller shaft speeds are below 43 Hz.

If the transmission is taken out of neutral before 2 seconds has elapsed, or either propeller shaft speed increases above
the limit, the shift will be suspended and the 4L indicator will continue to flicker until the requirements are met again or
the 4H/4L switch is returned to the original position. However, if the initial switch position is “4L”, “4L” indicator remains
on. If the shift requirements are met, the shift motor attempt to shift again.

Range Change

When the shift requirements are met, the motor rotates to the appropriate direction (as determined by the selector
switch) until one of the following occurs:

1. The motor reaches its destination.

2. The motor is on for 5 seconds without reaching its destination. The shift has failed and the TOD will respond as

default mode.

3. A fault occurs with either the motor or position encoder. Refer to the diagnosis requirement.

When the motor is energized, the Ignition, 4H/4L switch, propeller shaft speeds, and transmission neutral inputs are
ignored.

Shift operation is only allowed when some conditions are satisfied. These shift conditions should be satisfied for 2
seconds before starting motor. The motor has three seconds of delay at its initial operation to do trouble diagnosis.
Once the motor starts, the shift conditions are no longer checked.

Shift conditions are as follows:

- Normal battery voltage and shift motor for all gears
- Shift operation between 2H/4H and 4L is only available when the vehicle speed is below 43 Hz.

- No defective speed sensor

- The selector lever should be in “N” position (in case of manual transmission, the clutch pedal should be depressed).

ELECTRIC SHIFT SYSTEM OPERATION

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

TOD

STAVIC - 2004.09

Indicator Function on Shifting

Once a range change has been initiated the 4L Indicator will
begin to blink at a rate of 0.3 seconds on, 0.3 seconds off until
the shift is completed or canceled.

4L Indicator illuminates as below figure.

Electric Shift Default Mode

If the motor fails to reach its destination, the TOD will attempt
the following (in order):

1. The TOD will wait 3 seconds then attempt the shift again.

2. If the second attempt to reach the destination fails the

TOD will wait 3 seconds then attempt to rotate the motor
back to the original position. If successful, all future shifts
will be inhibited until the Ignition is cycled.

3. If the attempt to return to the original position fails, the

TOD will wait 3 seconds then attempt to rotate the motor
to the original position again. If the second attempt to
return to the original position is successful, the “4WD
CHECK” indicator will be illuminated, and all future shifts
will be inhibited until the Ignition is cycled.

4. If the second attempt to return to the original position

fails the motor will be turned off, the “4WD CHECK”
indicator will be illuminated, and all future shifts will be
inhibited until the Ignition is cycled.

0.3 seconds

Shift completed

(4H

→

→ 4L)

Shift Conditions

Shift is allowed only when certain conditions for the vehicle are satisfied. This means that the shift conditions must
satisfy the operating conditions for 2 seconds before motor starts and 2 seconds of delay at initial stage is to diagnose
the system.

The shift requirements are as follows:

- There should be no fault with battery voltage and shift motor for all shifts.
- Shift between 4H and 4L is operated only under the vehicle speed of below 43 Hz.
- There should be no fault with speed sensors.
- Transmission must be in neutral position (In case of manual transmission, the clutch pedal should be depressed).

Motor Controls

• The shift steps have the sequence of 4H

→ 4L and 4L → 4H → 2H. TCCU operates the shift motor until it reads

required position code. If it detects the faulty code, the system is operated with the compensation mode.

• Once the shift operation is started, it is completed regardless of ignition power. If there are not operating signals from

position sensor, the shifting failure due to timeout occurs. This failure appears when the shifting time between 2H
and 4H and between 4H and 4L is delayed over 5 seconds compared to normal shift. Once the shifting time exceeds
the specified time, TCCU cannot properly supply the voltage to shift motor and is operated in compensation mode.

• Even though the system recognize a fault before motor starts, it is considered as fault.

• Motor stops operation when it reaches at target range.

Compensation Mode

The motor stops when the encoder related troubles are detected during shift operation. It moves toward LOW-HIGH
direction for 5 seconds so that the motor is not left in unidentified position.

0.3 seconds

(4L

→

→ 4H)

Content .. 351 352 353 354 ..