1. 4 Wheel Drive (JTEKT) General course information
Target group: Instructors, Technicians
Target of the course: To get the general knowledge and system feature for the newly developed 4 wheel drive system.
Mandatory pre-courses: 4WD
To understand the system features and general knowledge for the 4 wheel drive system applied in XM.
Material:
Training vehicle (XM)
Training Part (T/F, Coupling)
Hi-scan Pro / GDS
Instructors guide
Trainees textbook / File
Practice sheets
(Practice preparation)
Workshop manuals
Certificates
Nameplates
(Paper for notes)
(Pens etc.)
Method:
Lecture
Practice
Task
Lead over:
Let’s start from the specification of ITCC.
4 Wheel Drive (JTEKT)
Copyright ⓒ 2009 All rights reserved. No part of this material may be reproduced, stored in any retrieval system or transmitted in any form or by any means without the written permission of Kia Motors Corporation.
Technical Writing: Mr. Eric Song, March. ‘09

2. Specification Specification Items Description Maker
Receiving the data from sensors in real time, the 4WD control module will control the driving torque of front and rear wheel depending on the road and driving condition controlling the magnetic clutch built in the 4WD coupling with duty cycle. It has a characteristic to cope with the tight corner braking effect and drive line wind up phenomena for stable driving performance.
The system supplier is ‘JTEKT’, Japan maker which is applied in Kia vehicles for the first time in XM and basically the system feature is similar to the existing ‘FF base - 4 wheel drive system’ on KM (SPORTAGE).
As for the lubricant, a specific oil, JWS 3309 (a kind of automatic transmission fluid mostly used in Aisin Co.,) has to be used, however it is maintenance free so that it is not necessary to replace.
As same as one for KM, the ITCC is not repairable so that it has to be replaced with the assembly.
The transfer is attached on the transmission (M/T or A/T) and it has two variants. Refer to the another page for more detail information.
To understand the general specification of ITCC.
Material:
Trainees textbook
Method:
Lecture
Lead over:
Let’s have a look at the feature of transfer case.
Specification
* ITCC: Intelligent Torque Controlled Coupling
Items
Description
Maker
JTEKT (Japan) : Toyoda Koki Automotive Systems
Operation voltage
12V
Torque output
0 ~ 1,320Nm
Weight
9kg
Housing Material
Aluminum
Oil
JWS 3309 (Permanent use), liter
Resistance (magnetic clutch)
2.4±0.2Ω (25℃)
ITCC
Instructor note:
‘JTEKT’ ITCC is being applied in Hyundai VERACRUZ. Due to the fact that the mapping algorithm (confidential) for all driving condition is programmed by system vender, we cannot give any specific threshold value, e.g. the vehicle speed / magnetic clutch duty ratio etc. Therefore, note that all specific data shown in this manual has been acquired from the driving experience and test result so that it may not match exactly with the result what you experienced.
Rear Differential

3. 1 axis type for R or θ engine Lubricant: Hypoid gear oil (SAE 75W/90)
Transfer case
In order to cope with high capacity and lower weight, two variants exist in the transfer case. 2 axis type transfer for Lambda engine is being applied in KM (SPORTAGE). 1 axis type transfer for R engine or Theta engine which was developed newly, has lower capacity but the weight is lower as well as the lubricant quantity, and the size is smaller than 2 axis type.
Able to identify the transfer case for two types.
Material:
Trainees textbook
Training Parts
Method:
Lecture
Lead over:
Let’s see the difference from the existing 4WD system.
Transfer case
2 axis type for λ engine
1 axis type for R or θ engine
Lubricant: Hypoid gear oil (SAE 75W/90)
0.7ℓ
0.6ℓ

4. Comparison Comparison SORENTO (BL) SPORTAGE (KM) XM System EST TOD ITM
Minimized number of sensor for control and the most recently updated logic was applied for 4WD system. The hardware was reinforced for better performance and durability.
As same as KM, 4WD lock mode has been added but note that it is available when the vehicle speed is lower than 30kph.
Two main signals (wheel speed and TPS) via CAN input to the 4WD control module to distribute the torque. However, the steering angle sensor was eliminated. (‘JTEKT’ system does not use the steering angle signal) It will be the most big difference comparing to the existing 4WD system in KM. The 4WD control module can calculate indirectly with the logic built in controller receiving the wheel speed sensor signal in order to prevent the tight corner brake effect without the steering angle sensor.
Diagnosis with scan tool
Only the DTC checking was possible with scan tool and there was no service data menu in case of the previous 4WD system control module for BL and KM. But in case of XM, following several data can be inspected in the ‘current data’ menu of the scanner.
- Engine speed (rpm), Vehicle speed (km/h) signal through CAN,
- TPS (%) signal through CAN,
- Ignition and Battery voltage (V),
- Computing command torque (Nm),
- Computing clutch duty (%), Heat energy (℃)
Also, several functions for ‘Actuator test’ were newly added from XM vehicle.
To understand the difference from the existing 4WD system.
Material:
Trainees textbook
Method:
Lecture
Lead over:
Let’s see the power flow and general caution when tow the vehicle.
* ITCC: Intelligent Torque Controlled Coupling
**MPS: Motor Position Sensor
Comparison
SORENTO (BL)
SPORTAGE (KM) XM
System
EST
TOD
ITM
*ITCC
Mode
2H-4H-4L
AUTO-LOW
4WD Lock
Shift type
Switch - 2H
2WD driving
Automatically shifted
Automatic distribution
(2WD↔4WD) 4H
4WD High (1:1) 4L
4WD Low (2.48:1)
Shift on the fly
Must stop (Auto↔Low)
Possible while driving
Input sensors
Speed sensor, MPS
Speed sensors(2EA) **MPS
Wheel speed sensor
Steering angle sensor
TPS
Maker
Borg-Warner(USA) ←
JTEKT (Japan)
Diagnosis
DTC only
DTC, Current data, Actuator test

5. Power flow Sensor ECM ITCC Power flow ・4 Wheel speed
Depending on the current controlled amount by control module, the pushing force toward the main cam will be varied in order to distribute the engine torque to front and rear wheels.
Due to the fact that all engineering mapping (confidential data) is done by system supplier, the specific control logic cannot be explained in detail in this training manual, however, followings are the general concept for the torque distribution control.
Generally speaking, the duty ratio of coil is proportion to the amount of throttle opening ratio. Oppositely, it is inverse proportion to the amount of steering angle and vehicle speed. However, note that this is just based on the experience and driving test result, therefore, it does not match always under all driving condition.
Let’s see the mapping strategy of normal driving condition.
Depending on the TPS ratio and vehicle speed, the system calculates the target torque. Based on this, the target current and duty ratio also will be calculated so that the torque will be distributed.
Next, there is condition that the slip (between front and rear) occurs. If the slip between front and rear occurs, it causes the damage on the coupling. Therefore, the system tries to minimize the slip amount. Based on the slip data and vehicle speed, the target torque, current and duty ratio will be decided.
To understand the general control principle and power flow.
To know the general cautions while towing the vehicle.
Material:
Trainees textbook
Method:
Lecture
Lead over:
Let’s have a look at the internal structure of ITCC.
Power flow
Sensor
・4 Wheel speed
・Throttle Position
・Brake signal
Current
ECM
When tow the car equipped with the ITCC, it is recommended to use following two methods.
If the power-train or chassis system has a problem, ‘flat bed truck’ method is recommended to use.
Engine
Flat bed truck
Wheel lift type truck
Rear diff.
Transfer
Front diff.
Transaxle
ITCC
The method in below is prohibited to use, otherwise it will make a severe damage on the car.

6. EMC operation Section view Ball Control Cam Main Cam Shaft Front H/G
The main principle of the magnetic clutch operation is the same as one for the previous models. Depending on the current flow amount in the magnetic coil, the distributed torque to rear wheel will be varied. That is, the pushing force of apply cam toward the multiple clutch pack is changed by the EMC duty rate. Under normal condition, maximum 5A is applied in the coil. If EMC coil is failed, only 2WD will be available and the coil standard resistance is 2.4±0.2Ω (25℃)
Three kinds of DTC has been defined regarding the EMC coil as follows.
- EMC over current (P1755)
- EMC internal error (P1756)
- EMC PWM out of range (P1757)
For more detail information, please refer to the section of DTC list in this manual.
To understand the internal structure of ITCC.
Material:
Trainees textbook
Method:
Lecture
Lead over:
Let’s see the input/output factors as well as CAN interface.
EMC operation
Main Clutch
Pilot Clutch
Electro magnetic Coil
Ball
Control Cam
Main Cam
ECU
Zero current
Shaft
Shaft (Rear Wheels)
Main Cam
Armature
Pilot Cam
Front H/G
Magnetic Flux
Pilot Cam
ECU
Torque
Rear H/G
Input
Main Cam
Armature
Control Clutch
Electro-magnetic Coil
Current flows
Output
Main Clutch

7. EMC (Electromagnetic Clutch) Battery & Ignition Power
Inputs & Outputs
If it is not possible to read or write the data on EEPROM for more than 3 times, this DTC will be memorized and the default torque control will be the same as 4WD lock mode.
All DTC may not be erased just by removing the control module or battery. It is only available to reset by scan tool. In addition, no K-line for the diagnosis with the scanner exists in 4WD control module but it will be implemented via CAN line as shown in the picture.
ABS Active signal
To guarantee the safety while ABS is operated and for more accurate ABS control, the EMC duty rate will be zero (2WD state) when ABS is operated. This ABS active signal will input through CAN from ABS or ESC control module and the 4WD control will be restored normally as soon as ABS control is finished.
ESC Active signal
While ESC is activated, the maximum torque for rear wheels will be restricted by 4WD control module for more effective TCS control.
Variant coding
No additional variant coding procedure is required by scanner, instead the corresponding software (for diesel, gasoline, A/T, M/T) will be automatically chosen when replace the control module.
4WD Lock lamp and Warning lamp driving
These lamps are driven via CAN line from 4WD control module to the cluster, that is no independent terminals exist in the control module for the lamps.
To understand the input signals and output actuators.
To know the CAN interface in 4WD control system.
Material:
Trainees textbook
Training vehicle
Method:
Lecture
Lead over:
Let’s see the function and feature of 4WD lock mode.
Inputs & Outputs
Inputs
Outputs
4WD Control Module
(ITCC CM)
EMC (Electromagnetic Clutch)
Battery & Ignition Power
4WD Lock Switch
Wheel Speed Sensor Signal, TPS (APS), Engine speed, Engine torque, ABS/ESC Active signal, Brake Signal
4WD Lock mode lamp 4WD Warning Lamp
ECM
ESC
Diagnosis
Cluster

8. 4WD Lock Mode 4WD Lock Mode Mode Torque Distribution Remark Auto
Auto mode
Upon driving with the constant straight ahead condition, it is controlled with 2WD (FWD) status. The torque distribution rate (Front: Rear – 100:0 ~ 50:50) will be calculated and decided by 4WD control module depending on the driving conditions (Full acceleration, Steering, Low friction road)
Lock mode
Mostly this mode is used while driving on the off-road or icy road in order to minimize the slip amount between the front and rear wheels. The torque distribution is set to 50:50 upon pressing the 4WD lock button. However, this mode is automatically released and converted to auto mode if the vehicle speed exceeds 30kph. If the 4WD lock switch is pressed while driving with the vehicle speed more than 30kph, it does not be shifted to lock mode but controlled by auto mode. However the 4WD lock lamp still keeps ON at that time. As the vehicle speed drops less than 30kph, the lock mode is activated automatically. In addition, even this switch is failed, no DTC has been defined. Also you cannot find the 4WD lock switch signal in the current data of the scanner.
Intelligent lock
Even if the 4WD lock switch is pressed and the vehicle speed is lower than 30kph, the system does not fix the torque distribution ratio (50:50) when the vehicle is turned. That is, the driver’s intention is neglected but the 4WD lock lamp will still remains ON. This is to prevent the binding noise while turning and it is referred to as ‘intelligent lock’. Note that this logic is being already applied in the 4WD system for KM (SPORTAGE).
4WD failure lamp
It will be turned on (‘not blink’) when the DTC is stored in the control module.
Instructor note:
4WD lock symbol – the symbol shown in the switch is based on the vehicle built in pilot production. The ‘x’ mark on the propeller shaft may give a misunderstanding that 4WD will be cancelled upon pressing this switch to the customer. Therefore, in order to prevent the misunderstanding, the symbol on the switch will be changed. That is, ‘LOCK’ will be added as same as the logo in the cluster from the mass production. (In pilot version training vehicle, you may not possible to find ‘LOCK’ on the lamp in the cluster)
To understand the function of 4WD lock mode switch.
To know the feature of lamps related to the 4WD system in XM.
Material:
Trainees textbook
Training vehicle
Method:
Lecture
Lead over:
Let’s see the location of main components.
4WD Lock Mode
Mode
Torque Distribution
Remark
Auto
0:100 ~ 50:50 -
4WD Lock
50:50 (fixed)
30kph or less
[4WD Lock Switch]
[4WD failure Lamp]
[4WD Lock Switch Lamp]

9. Components TCM Components [Wheel speed sensor] [ITCC] [Control Module]
Wheel speed sensor signal
This signal is used to detect the rotating speed difference between front and rear wheels. The average value both left and right wheel speed will be used for front and rear wheel speed. It will be controlled by 2WD cutting the current of EMC upon the system failsafe. Be sure that this signal comes from ABS (ESC) control module through CAN. That is the reason why the DTC for wheel speed senor has a initial symbol of ‘U’ and ABS is applied as a standard option.
To know the location of the components.
Material:
Trainees textbook
Training vehicle
Method:
Lecture
Lead over:
Let’s have a look at the DTC definition and it’s detecting condition.
Components
[Wheel speed sensor]
TCM
[ITCC]
[Control Module]

10. DTC list DTC List DTC Items Detected Condition Failsafe P0605
EMC over current (P1755)
Monitoring shunt current on coupling and when more current than setup conducted, system will be stalled. The commanded torque to EMC will be zero Nm and the power supply relay (built in control module) for EMC will be off to protect the EMC circuit.
- Detection condition: Coil current is higher than 6A for 0.1s or more.
- Restoring condition: IG off  on
EMC internal error (P1756)
When the current level is normal (no over current), following conditions must be met for more than 2 seconds to detect the above DTC.
Condition 1: PWM Duty ≥ 90%, Coil current ≤ 0.1A
Condition 2: PWM Duty ≤ 10%, Coil current ≥ 3.0A
- Failsafe: The commanded torque will be zero and the supply voltage relay will be off.
EMC PWM out of range (P1757)
1) Condition 1: While primary checking, relay off outputs, the supply voltage is higher than 9V for more than 1s.
2) Condition 2: Ignition 1 voltage is higher than 7.5V, relay on outputs, supply voltage is lower than V for more than 1s.
Accelerator Pedal Position Sensor (U0100)
This data also comes from the other control module through CAN so the DTC has a symbol of ‘U’.
- Failsafe: In case of throttle signal error, system will be temporality stalled and APS value will be controlled by 0%.
* While Auto mode: Command torque to EMC will be zero Nm
* While 4WD Lock mode: Command torque to EMC will be 1,000N.m
- Detection cycle: 0.005s
- Detection condition:
1) Condition 1: APS signal receiving value is invalid (over 99%) for more than 0.5s.
2) Condition 2: APS data cannot be received in 0.5s.
Restoring condition: IG off  on OR received valid value.
To understand the DTC detection condition.
Material:
Trainees textbook
Training vehicle
Scanner
Method:
Lecture
Lead over:
Let’s see the DTC details about wheel speed signal.
DTC list
DTC
Items
Detected Condition
Failsafe
P0605
EEPROM Error
If EEPROM data cannot be read or written 3 times
4WD Lock mode
P1755
EMC Over Current
Coil current ≥ 6A, more than 0.1 second
Torque = 0Nm (EMC power off)
P1756
EMC Internal Error
No over current error case 1 : PWM Duty ≥ 90%, Coil current ≤ 0.1A over 2s case 2 : PWM Duty ≤ 10%, Coil current ≥ 3.0A over 2s
P1757
EMC PWM Out of Range
case 1 - EMC OFF signal output EMC voltage ≥ 9V, 1 second or more
case 2 - EMC ON signal output EMC voltage ≤ 2V, 1 second or more
U0100
Accelerator Position signal error
case 1 - Abnormal APS signal for 0.5 second or more
case 2 - No APS signal for 0.5 second or more
APS= 0%
AUTO mode  0 Nm Lock mode  100Nm
U0121 (ABS)
U0122 (ESC)
Wheel speed signal error
case 1 - Abnormal wheel speed signal (511kph) for second or more case 2 - No signal for 0.5 second
U0001
CAN Bus Off
CAN communication failure