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01-213680-01
Pressure Modulation ▶
To provide a higher level of shift comfort and durability, the hydraulic pressure in the shift related friction
elements of the transmission must be matched accurately to the input torque to transmission. This
hydraulic pressure is composed of a hydraulically pre-set basic pressure and a control pressure which is
set by one of the variable bleed solenoids.
The transmission input torque can be directly calculated from the following operating parameters:
engine torque signals
engine speed or any signal transmitted from ECU through CAN lines
converter slip -
-
-
Separate pressure characteristics for each gear change make it possible to adapt precisely to the
particular shift operation.
5) Shift Mode Selection by TCU
The driver can select Standard (S) or Winter mode (W) with the mode switch. TCU automatically
changes the shift mode according to the transmission oil temperature, uphill or downhill gradient, and
altitude to keep the good driving conditions.
Standard Mode (S) ▶
Uphii and Downhill Mode ▶
Altitude Mode ▶ Standard Mode is selected when setting the mode switch in Standard (S) position with the gear select
<0093008c009d008c0099004700900095004702c8006b02c9004700880095008b0047009b008f008c0047009b009900880095009a00940090009a009a00900096009500470096009000930047009b008c00940097008c00990088009b009c0099008c004700
9000950047009500960099009400880093004700960097008c>rating range. Proper shift timing
provides the optimized fuel economy and good driving conditions.
In this mode, the operating points of torque converter lock-up clutch and the shifting points are adjusted
according to the vehicle weight.
In this mode, the shifting points are automatically adjusted according to the altitude to compensate the
engine torque changes due to barometric pressure and temperature.
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01-22
Winter Mode (W) ▶
Low Range Driving Mode ▶
Warm Up Mode ▶ When the Winter mode is selected, the second gear is engaged to start off the vehicle easily to prevent
wheel spin on slippery surfaces and WINTER mode indicator comes ON. The first gear is not available
in this mode.
When the vehicle is in 4L driving mode, the transmission uses a different shift mode to optimize the low
range driving. Similar to Winter mode, the first gear is not available.
This mode is normally used when the transmission oil temperature is below 20°C.
<007b008f008c0047009b009600990098009c008c0047008a00960095009d008c0099009b008c00990047008a0088009500950096009b00470089008c004700930096008a0092008c008b0054009c009700470089008c00930096009e00470059005700b600
6a0047009b00960047009700990096009d0090008b008c0047>the warming up process of
transmission.
Hot Mode ▶
<0070008d0047009b008f008c0047009b009900880095009a00940090009a009a00900096009500470096009000930047009b008c00940097008c00990088009b009c0099008c00470090009a00470089008c009b009e008c008c0095004700580058005700
b6006a004700880095008b00470058005b005c00b6006a0053> the system provides the cooling
and reduces the load to the transmission. This is called Hot Mode.
Above 110°C:
Above 130°C:
Above 145°C: -
-
-
In Hot Mode, any of shift mode is not available.
Cruise Control ▶
When the cruise control is activated, the engine ECU requests the downshift to increase the engine
brake effect.PWM fan ON
the engine torque is reduced and WINTER indicator is blinking
the transmission is held in Neutral (N) gear until the oil temperature falls below
120°C (Final protection)
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03-73170-01
2) Function of N Switch
(1) Aids a smooth start of the vehicle by raising the RPM during the gear
shifting when the engine is cold.
When the vehicle is trying to start from the stopped state (vehicle speed below 3 km/h), the N switch
determines the shifting timing by using the clutch switch and the N switch. It raises the engine RPM (100
~ 200 rpm). Operation conditions are as follows.
The vehicle speed is at the stopped state (Vehicle speed below 3km/h detection).
While depressing the clutch (Clutch switch detection).
The gear lever is at a position other than neutral (N switch detection).
Start the vehicle while depressing the clutch pedal (Clutch switch detection).
The RPM increases in accordance with the temperature of the engine coolant
(Engine coolant temperature sensor detection). -
-
-
-
-
appx. 100 rpm increase
appx. 100 ~ 170 rpm increase
<008800970097009f00550047005f005700b6006a0047004f0095009600990094008800930047009b008c00940097008c00990088009b009c0099008c00470096008d0047009b008f008c0047008c0095008e00900095008c0047008a009600960093008800
95009b005000610047008800990096009c0095008b00470059>00 rpm ·
·
·
When the gear has been smoothly shifted and the vehicle speed exceeds 3km/h, it returns to the
previous operation interval of the engine RPM. -
In case of Actyon, the N switch signal is transmitted to the instrument panel, and then the instrument
panel transmits it to the engine ECU through the CAN communication.
Vehicle Made After 04.09.15 Actyon
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03-8
Variant Coding Options
(2) Detects the position of the shifting lever for the HDC operation
among ABS functions.
The HDC function operates only if the M/T shift lever is in forward or reverse position. Please refer to the
ABS section for the specific information related to the HDC.
Variant Coding Related to N Switch ▶
The N switch transmits information to the ECU through the CAN communication while New Rexton is
connected to the ECU through wires. Thus, if you set the variant coding in the engine ECU, you must do
it differently, and you must set the variant coding differently according to the vehicle category and
specification as below.
Neutral Signal Input None / Wire / CANWire /
Actyon & Kyron models with
manual transmission
New Rexton model with manual
transmission Manufactured after
04.09.15
BODY IN: after 154600
Automatic transmission & Rodius
model with automatic transmission
before 2006
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11-8
1. OVERVIEW
The ESP (Electronic Stability Program) has been developed to help a driver avoid danger of losing
control of the vehicle stability due to understeer or oversteer during cornering. The yaw rate sensor,
lateral sensor and longitudinal sensor in the sensor cluster and the steering wheel angle sensor under
the steering column detect the vehicle conditions when the inner or outer wheels are spinning during
oversteer, understeer or cornering. The ESP ECU controls against oversteer or understeer during
cornering by controlling the vehicle stability using input values from these sensors and applying the
braking force to the corresponding wheels independently. The system also controls the engine power
right before the wheel spin synchronized to decelerate the vehicle automatically in order to maintain the
vehicle stable during cornering.
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11-94890-10
ESP OFF switch
Located on the left side of
instrument panel.
Rear wheel speed sensor
Located on the both ends of
rear axle.Front wheel speed sensor
Located on the hub assembly.Sensor cluster
Located at the bottom of center
fascia panel.
Steering wheel angle sensor
Located on column shaft with
contact coil.HECU assembly
Located near the brake booster
in engine compartment and
contains the pressure sensor.
2. COMPONENTS
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11-10
3. FUNCTION
1) Term Definition
ABS: Anti-Lock Brake System ▶
When the brake pedal is abruptly depressed, the HECU calculates the slip ratio of each wheel based on
information received from the wheel speed sensors and controls the hydraulic module data quickly and
precisely in order to maintain the friction between the road surface and tire optimal (static friction).
Therefore, by keeping the friction between the road surface and tire optimal, it is possible to obtain
following effects: Enhanced steering stability, improved direction stability, reduced stopping distance and
etc.
EBD: Electronic brake-Force Distribution ▶
This is to detect the tire speed from the wheel speed sensor in order to supply the braking pressure to
the rear tires individually. In other words, the HECU measures the tire deceleration speed continuously
and controls the rear inlet valve on the hydraulic modulator to obtain optimal braking force as much as
possible. Thereby, stopping distance, braking effect and straight stability are improved.
ESP: Electronic Stability Program ▶
This is used to make the vehicle stabilized to recognize the emergency driving conditions, and to control
the brake for each wheels and the engine power when the brake system or acceleration will not work
any more in dangerous circumstances.
TCS: Traction Control System ▶
When the wheel is slipping due to an excessive engine torque while starting off or driving, this controls
the driving force (braking force + engine torque) in order to prevent the wheel from slipping through the
engine or brake control.
AYC: Active Yaw Control ▶
This has been developed to help a driver avoid danger of losing control of the vehicle stability due to
understeer or oversteer during cornering, which is a part of the ESP function.
HBA: Hydraulic Brake Assistant ▶
Developed based on the fact that elderly drivers depress the brake pedal too soft even when hard
braking is necessary, this an assist system to operate the HECU drive motor immediately and apply high
braking force to the wheels when the brake pedal is depressed softly and the vehicle should be braked
in emergency.
ARP: Active Rollover Protection ▶
This is a supplementary device for safety in ESP system and can help minimize the rollover accidents by
detecting a potential rollover situation through the brake and engine control when making sudden lane
change or turning sharply by adding only the software, without any separate device or switch.
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11-16
2) Operation of ESP System
The ESP (Electronic Stability Program) has been developed to help a driver avoid danger of losing
control of the vehicle stability due to understeer or oversteer during cornering. The yaw rate sensor,
lateral sensor and longitudinal sensor in the sensor cluster and the steering wheel angle sensor under
the steering column detect the vehicle conditions when the inner or outer wheels are spinning during
oversteer, understeer or cornering. The ESP ECU controls against oversteer or understeer during
cornering by controlling the vehicle stability using input values from these sensors and applying the
braking force to the corresponding wheels independently. The system also controls the engine power
right before the wheel spin synchronized with the ASR function to decelerate the vehicle automatically in
order to maintain the vehicle stable during cornering.
(1) Under steering
What is understeering? ▶
Understeer is a term for a condition in which the steering wheel is steered to a certain angle during driving
and the front tires slip toward the reverse direction of the desired direction. Generally, vehicles are
designed to have understeer. It is because that the vehicle can return back to inside of cornering line
when the steering wheel is steered toward the inside even when the front wheels are slipped outward.
As the centrifugal force increases, the tires can easily lose the traction and the vehicle tends to slip
outward when the curve angle gets bigger and the speed increases.