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Vehicle Control System

Safety Precaution

Sinse Electric Vehicle contains a high voltage, battery mishandling the high voltage system or vehicle may lead to a serious accident
including electric shock and electric leakage.

• Be sure to shut off the high voltage by removing the safety plug before inspecting or repairing the high voltage system(Refer to
“High Voltage Shut-off Procedures”).
• A responsible worker should keep removed safety plugs to prevent it from being connected by mistake.
• Keep away from any metal objects (watch, ring etc.) while working on the high voltage system, as they may cause serious accidents
like electric shock.
• Before beginning to work on the high voltage system, workers should wear personal protective equipment to prevent safety
accidents(Refer to “Personal Protective Equipment”).
• At any time, do not allow workers not wearing personal protective equipment to touch the high voltage system. High voltage
components should be covered with an insulation sheet to prevent safety accidents.
• Use insulation tools when working on the high voltage system.
• Place removed high voltage components on an the insulation mat.
• Check that voltage between the high voltage terminals is below 30V after removing the safety plug.

• All the high voltage wiring and connectors are in orange.

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• A caution label for high voltage is attached to the high voltage components
• High voltage components : High Voltage Battery, Power Relay Assembly (PRA), Quick Charge Relay Assembly (QRA), Motor,
Power Cable, BMS ECU, Inverter, LDC, On-Board Charger (OBC), Main Relay, Pre-charge Relay, Pre-charge resistor, Battery
Current Sensor, Safety Plug, Main Fuse, Battery Temperature Sensor, Busbar, Charge Port, A/C Compressor, Electric Power
Control Unit (EPCU), High Voltage Heater, High Voltage Heater Relay etc.

• Inform of possible danger of high voltage by placing a "high voltage caution" sign on the vehicle as in the image below.
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Personal Protective Equipment

Name Illustration Description

Insulation gloves Used when inspecting or working on the high voltage
components
[Insulation performance : 1000V / 300A or above]
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Insulation shoes

Used when inspecting or working on the high voltage

Insulation clothes
components

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Insulation helmet

Safety glasses

Used in the following cases :

• During Removal & installation or inspection of the high
voltage battery terminals or wiring, which spark might happen.
• When working on the high voltage battery pack assembly.

Face shield

All removed high voltage components are placed on an

Insulation mat
insulation mat to prevent safety accidents.

Insulation sheet is used to cover high voltage components to

Insulation sheet protect people not wearing personal protective equipment from
safety accidents.

Warning tape Used for infomring that it is dangerous to come over this line.
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Personal Protective Equipment Inspection

• Check that the personal protective equipment is not damaged.

• Check that the insulation gloves are not torn or damaged.
• Wear the insulation glove after removing moisture.

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Fold the insulation glove as above.
Fold again 3~4 times to make it airtight.
Squeeze the inflated glove to see if the glove is torn or damaged.
Caution when repairing the power cable

• When installing the high voltage terminal, insulate the terminal using insulation tape.
• Tighten the high voltage screw with specified torque.
• Be careful that the (+) terminal does not contact the (-) terminal.

Precautions when handling high voltage battery

• Battery Control System - Refer to "High Voltage Battery Handling Guide"

Precautions in case of fire in High Voltage Battery System

• Turn OFF the Button Start. Then keep the Smart Key 2m or farther away from the vehicle to prevent unintended engine start.
• If the fire is at initial stage, quickly turn OFF the Safety Plug
(refer to "High Voltage Shut-off Procedure").
• If fire broke out indoors, ventilate the area to clear out hydrogen gas.
• If fire can be put out, then do so using a CO₂ fire extinguisher. If this is not available, then use water or other types of fire extinguisher.
• CO₂has high insulation characteristics against electricity, so it is appropriate for electricity (C Rating) related fire.
• If fire cannot be put out, evacuate to a safe location, notify the fire department and do not approach the vehicle until the fire has been
extinguished.
• Turn OFF the vehicle Key in case of vehicle submersion/collision, and then exit the vehicle as quickly as possible.

Precautions in case of high voltage battery gas and/or electrolyte leakage

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• Turn OFF the Button Start. Then keep the Smart Key 2m or farther away from the vehicle to prevent unintended engine start.
• If the fire is at initial stage, quickly turn OFF the Safety Plug.
(refer to "High Voltage Shut-off Procedure").
• Gas is hydrogen and alkali vapor. If the fire occurred indoor, ventilate the area immediately and evacuate to a safe location.
• If leaked liquid comes in contact with your skin, neutralize the area immediately with boron, and then clean with running water or saline
solution.
• If leaked vapor or liquid gets in your eye, immediately clean with running water, then get medical attention.
• In case of gas leakage due to high temperature, do NOT use the battery until the high voltage battery cools down to room temperature.

Precautions when handling vehicle after an accident

• Be sure to wear insulated gloves (or rubber gloves), protective goggles, insulated suit, and insulated boots.
• Do NOT touch the bare cable when its insulation covering has been peeled.
(refer to "Precautions When Handling Power Cable")
• In case of fire on the vehicle and if the fire can be put out, then do so by using a CO₂ fire extinguisher. If this is not available, then use
water or other types of fire extinguisher.
• If more than half of the vehicle is submerged, then do not attempt to approach high voltage components, such as the Safety Plug. If such
a component must be handled, then first relocate the vehicle to a safe location, then handle the component.
• if fire broke out indoors, ventillate the area immediately and evacuate to a safe location. because the gas id hydorgen and akali fumes.
• If leaked liquid comes in contact with your skin, neutralize the area immediately with boron, and then clean with running water or saline
solution.
• If high voltage needs to be shut-off, then refer to "High Voltage Shut-off Procedure" when handling relevant components.

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Preparations when servicing accident affected vehicle

• Insulated gloves (or rubber gloves), protective goggles, insulated suit, and insulated boots.
• Boric Acid Powder or Solution.
• CO₂ fire extinguisher or other fire extinguisher.
• Towel for cleaning electrolyte.
• Vinyl tape (for terminal insulation)
• Megaohm Tester (for checking high voltage insulation resistance)

Precautions when EV is unattended for a prolonged period

• Turn OFF the Start Button. Then keep the Smart Key 2m or farther away from the vehicle to prevent unintended engine start. (This is to
prevent rapid discharging of high voltage battery from dark current.)
• If the high voltage battery state of charge (SOC) is less than 30%, then do not leave the vehicle unattended for a prolonged period.
• If the vehicle is unattended for prolonged period, then fully recharge the battery via normal charging once every 3 months to prevent the
high voltage battery SOC from becoming 0.
• When checking the auxiliary battery for discharge status or when replacing the auxiliary battery, check for problem related to high
voltage battery SOC reset.

Hybrid Vehicle Refrigerant Recovery / Charging Precautions

• Since the electric compressor uses high-voltage, POE oil with high Volumetric Resistivity Should be used.
• Do not use the same A/C recovery / charging station as conventional belt-driven compressors.

If the POE oil in the system gets mixed with PAG oil, it may result in dielectric breakdown due to decreased volumetric resistivity and
inoperative A/C compressor, disabling the A/C compressor.

Vehicle Control System

High Voltage Shut-off Procedure

Be sure to read and follow the “General Safety Information and Caution” before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
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High voltage components : High Voltage Battery, Power Relay Assembly (PRA), Quick Charge Relay Assembly (QRA), Motor, Power
Cable, BMS ECU, Inverter, LDC, On-Board Charger (OBC), Main Relay, Pre-charge Relay, Pre-charge resistor, Battery Current
Sensor, Safety Plug, Main Fuse, Battery Temperature Sensor, Busbar, Charge Port, A/C Compressor, Electric Power Control Unit
(EPCU), High Voltage Heater, High Voltage Heater Relay etc.
1. Turn the ignition switch OFF and disconnect the negative (-) terminal of the auxiliary battery.
2. Remove the cover (A) on the floor carpet of the rear seat.

3. After loosening the nut, remove the safety plug service cover (A).
Safety plug service cover mounting nut :7.8 ~ 11.8 N.m (0.8 ~ 1.2 kgf.m, 5.8 ~ 8.7 lb-ft)

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4. Remove the safety plug (A).

Remove the safety plug in the follwing order.

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5. Wait at least 5 minutes or until the capacitor in the high voltage system is fully discharged.
6. Measure the voltage between the inverter terminals to check that the capacitor in the inverter is discharged completely
(1) Lift the vehicle.
(2) Remove the high voltage battery lower cover (A) by loosening the bolt.

(3) Remove the high voltage cable (A).

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(4) Measure the voltage between the inverter terminals.
Less than 30V : High voltage circuit properly shut
More than 30V : Faulty on high voltage circuit
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If measured voltage is over 30V, check that the safety plug is removed completely. If it is is over 30V even though the safety plug
has been removerd, there may be a serious problem in the high voltage circuit. In this case, check DTC and never touch on the
high voltage system.
Vehicle Control System

Description
Electric vehicle is a vehicle that drives on electric energy. Unlike combustion engine vehicle, it does not use fossil fuel to generate drive force
but uses the electric energy stored in the high voltage battery mounted in the vehicle to power the vehicle. While combustion engine vehicle
generates emission gas, electric vehicle is an eco-friendly vehicle that has zero emission.
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Electric vehicle operation principle and recharge method

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Motor Drive Control
• VCU: Calculates motor torque command with consideration to usable battery power, usable motor torque, and driver demand (APS,
Brake SW, Shift Lever).
• BMS: Provides usable battery power and SOC data for calculating motor torque command by VCU.
• MCU: Provides usable motor torque for calculating motor torque command by VCU.
Creates Inverter PWM signal to generate motor torque command received from VCU.
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Regenerative Brake Control

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• AHB: Calculates total brake force based on driver demand (BPS) and then divides the force into hydraulic brake force and demanded
regenerative brake force.
Monitors the regenerative braking result (VCU) and compensates hydraulic brake force.
• VCU: Calculates motor recharge torque command for regenerative braking by considering demanded regenerative brake force (AHB),
usable battery power (BMS), and usable motor torque, and calculates the actual regenerative brake force by using the actual motor
output torque (MCU).
• BMS: Provides usable battery power and SOC data.
• MCU: Provides usable motor torque and actual motor output torque data.
Creates Inverter PWM signal to generate motor torque command received from VCU.

A/C Load Control

• FATC: Sends AC/PTC power request to VCU when driver demands cooling/heating (AC SW).
A/C load is controlled within the power range allowed by VCU.
• BMS: Provides usable battery power and SOC data.
• VCU: Sends final FATC allowed power by using the battery information and FATC requested power data.
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Electric load power (12V) supply

• BMS: Provides usable battery power and SOC data.
• VCU: Determines LDC ON/OFF and operation mode based on the battery information and vehicle status.
• LDC: Converts high voltage into low voltage based on the command from VCU, and supplies power to vehicle's electric components
(same function as an alternator).

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DTE (Distance To Empty)
Calculates Distance To Empty
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Vehicle Control System

Schematic Diagram
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Vehicle Control System

Specification
Item Specification
Input Voltage 240 ~ 413V
Operation Voltage 9 ~ 16V
Cooling Type Water Cooled
Coolant Inflow Temperature Max. 65 °C
Operation Temperature -40 ~ 85 °C
Preservation Temperature -40 ~ 85 °C

Vehicle Control System

Components and Components Location

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1. Electric Power Control Unit (EPCU)
[ Inverter + LDC + VCU]

Vehicle Control System

Description

Electric Power Control Unit (EPCU) is a 80kW power transformer system. It is integrated with inverter, LDC, and VCU.
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- Inverter: It's a system that converts DC power from the high voltage battery to AC power supplied to the vehicle's drive motor.
- LDC (converter): It's a system that converts DC power from the high voltage battery to DC power (low voltage) for the vehicle's electric
components.
Vehicle Control System

Removal

• Use a fender cover to prevent damage on body paint.

• Take caution not to damage the connector and wiring when disconnecting.

• Be sure to read and follow the “General Safety Information and Caution” before doing any work related with the high voltage
system. Failure to follow the safety instructions may result in serious electrical injuries.
• Be sure to shut off the high voltage before doing any work related with the high voltage system(Refer to "High Voltage Shut-off
Procedure"). Failure to follow the safety instructions may result in serious electrical injuries.

Mark to prevent faulty connection between wiring connector and hose.

1. Shut off the high voltage.
(Refer to Vehicle Control System - "High Voltage Shut-off Procedures")
2. Remove the Auxiliary 12V Battery and tray.
(Refer to EPCU - "Auxiliary 12V Battery ")
3. Remove the power electric cover.
(Refer to Traction Motor System - "Power Electric Cover" )
4. Remove the high voltage joint box.
(Refer to High Voltage Distributing System - "High voltage joint box" )
5. Remove the ON-Board Charger (OBC).
(Refer to High Voltage Charging System - "OBC")
6. Disconnect the electric water pump outlet hose (A) and electric power control unit & Motor hoses(B).
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7. Disconnect the electric power control unit connector (A).

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8. Disconnect the Low Voltage DC/DC Converter "-" cable (A) and "+" cable (B).
Tightening torque :1.1 ~ 1.4 kgf.m

9. Disconnect the electric power control unit side power cable connector (A).

10. Remove chiller (A) after loosening the mounting bolts.

Tightening torque :0.8 ~ 1.2 kgf.m
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11. Remove the electric power control unit (A).

Tightening torque :5.0 ~ 6.5 kgf.m

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Installation
1. Install in the reverse order of removal.
2. Connect the 3-phase power cable of U, V, W in the correct position.

If the power cable is incorrectly assembled, it may result in serious damage in inverter, drive motor, and high voltage battery. In
addition, it may also cause injury to driver or service engineer. As a result, take caution when assembling the power cable.
3. Fill the coolant and then check the leakage.

Refill the motor cooling system with coolant and then perform the air bleeding using the GDS.
(Refer to Motor Cooling System - "Coolant")
4. Install the motor assembly then perform "Initialization of Automatic Resolver OffsetCalibration" procedure.

If "Initialization of Automatic Resolver Offset Calibration" is not reset after exchanging the motor, it may result in reduced max power
output as well as drive range.
(Refer to Motor & Reduction Gear - "Motor Position and Temperature Sensor")
Vehicle Control System

Description
The inverter drives the motor of an Electric Vehicle (EV). It changes the DC current of the high voltage battery to the AC current require to
drive the motor.
That is, it converts the DC power (+, -) from the high voltage battery into 3-phase AC power (U, V, W) and controls it vis the signal from the
control board to drive the motor.
During acceleration, the high voltage battery provides additional power to the motor. During deceleration, the energy generated by the motor
is used to charge the high voltage battery and there by increase the driving distance.
Main function
Class Item Contents Main iteam
• Current control
Generate the torque by controlling the amount and the
Control function Torque control • Rotor position and speed
direction of stator current according to the position of rotor
detection
Protection function Over temperature If excess the restrictive temperature of inverter and motor,
limit then limit the motor power
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limit the max motor power

according with inverter and motor
temperature
• Detection of disorders
associated with inverter
• Detection of problems related to the exernal inerface • Fault detection of performance
Failure detection
• Fault detection in the inverter related
• Inverter hardwere failure
detection
• Demand torque, Battery
condition, EWP, and other
Vehice driving The communication with the another controller of necessary receive information
Cooperative control
control information from the vehicle
• Inverter status information
transmission

Vehicle Control System

Block diagram
Traction motor control
Inverter provides the available torque to VCU for calculating the necessary torque and develops the PWM signal to make the necessary
motor torque calculated by VCU.

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Regenerative braking control
Inverter provides the available torque and the actual motor torque to VCU for calculating the necessary torque and develops the PWM signal
to make the necessary motor torque calculated by VCU.

Vehicle Control System

Description
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• High voltage (DC 360V) of the high voltage battery is converted low voltage (DC 12V) through the LDC for supplying power to electrical
components.
• Operation and operation mod of LDC are controlled by the vehicle control unit (VCU).
• The low voltage DC/DC converter is integrated into the EPCU.
System flow

Item Specification
Input High Voltage Battery (360V)
Output Auxiliary Battery (12V)
Purpose Auxiliary battery recharge and power supply to electric loads
Idle stop: Power supply is enabled
Characteristics
Temperature characteristics: Constant power

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Vehicle Control System

Specifications
▷ CMF45L-BCI
Item Specification
Capaticy [20HR/5HR] (AH) 45/36
Cold Cranking Amperage (A) 410 (SAE) /328 (EN)
Reserve Capacity (Min) 80

Vehicle Control System

Components
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1. Auxiliary 12V Battery 3. Battery tray
2. Battery mounting bracket

Vehicle Control System

Description
• The CMF(Closed Maintenance Free) battery is, as the name implies, totally maintenance free and has no removable battery cell caps.
• The CMF(Closed Maintenance Free) battery does not require water replenishment for the repair.
• The battery is completely sealed, except for small vent holes in the cover.
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Battery sensor
Battery sensor (A) is mounted on battery (-) terminal. It transmits battery voltage, current, temperature information to LDC. LDC controls
generating voltage by duty cycle based on these signals.

Electrical components power (12V) supply flow

• BMS ECU (Battery Management System Electronic Control Unit): Provide information (available battery power, state of charge)
• VCU (Vehicle Control Unit): Determine operation mod of the LDC according to battery status and vehicle status
• LDC (Low voltage DC/DC Converter): Supplies power to the vehicle electrical components after LDC is convert low voltage to high
voltage according to control of VCU.

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* APS: Accelerator pedal position sensor

Vehicle Control System

Removal
Battery & tray
1. Disconnect the battery terminals .
Tightening torque
(+): 7.8 ~ 9.8 N.m (0.8 ~ 1.0 kgf.m, 5.8 ~ 7.2 lb-ft)
(-): 3.9 ~ 5.9 N.m (0.4 ~ 0.6 kgf.m, 2.9 ~ 4.3 lb-ft)

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2. Remove the battery after removing a battery mounting bracket (A).
Tightening torque :8.8 ~ 13.7 N.m (0.9 ~ 1.4 kgf.m, 6.5 ~ 10.1 lb-ft)

3. Remove the battery tray (A) after loosening bolts.

Tightening torque :8.8 ~ 13.7 N.m (0.9 ~ 1.4 kgf.m, 6.5 ~ 10.1 lb-ft)

Batterty sensor
1. Disconnect the battery negative (-) cable.
2. Disconnect the battery sensor connector (A).
3. Remove the battery negative (-) cable after removing the bolt (B).
Tightening torque
(-) terminal: 3.9 ~ 5.9 N.m (0.4 ~ 0.6 kgf.m, 2.9 ~ 4.3 lb-ft)
(B): 26.5 ~ 32.4 N.m (2.7 ~ 3.3 kgf.m, 19.5 ~ 23.9 lb-ft)
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Installation
Battery & tray
1. Install in the reverse order of removal.

• When installing the battery, fix the mounting bracket on the tray correctly.

Batterty sensor
1. Install in the reverse order of removal.

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• For the vehicle equipped with a battery sensor, be careful not to damage the battery sensor when the battery is replaced or
recharged.
1) When replacing the battery, it should be same one (type, capacity and brand) that is originally installed on your vehicle. If a
battery of a different type is replaced, the battery sensor may recognize the battery to be abnormal.
2) When installing the ground cable on the negative post of battery, tighten the clamp with specified torque. An excessive tightening
torque can damage the PCB internal circuit and the battery terminal .
3) When recharging the battery, ground the negative terminal of the booster battery to the vehicle body.

Adjustment
Battery Sensor Recalibration Procedure
After reconnecting the battery negative cable, AMS function does not operates until the system is stabilized, about 4 hours. If disconnecting
the negative (-) battery cable from the battery during repair work for the vehicle equipped with AMS function, Battery sensor recalibration
procedure should be performed after finishing the repair work.
1. Turn the Ignition switch ON and OFF.
2. Park the vehicle for about 4 hours with the hood and all doors closed.

Inspection
Vehicle parasitic current inspection
1. Turn the all electric devices OFF, and then turn the ignition switch OFF.
2. Close all doors except the engine hood, and then lock all doors.
(1) Disconnect the hood switch connector.
(2) Close the trunk lid.
(3) Close the doors or remove the door switches.
3. Wait a few minutes until the vehicle’s electrical systems go to sleep mode.

For an accurate measurement of a vehicle parasitic current, all electrical systems should go to sleep mode. (It takes at least one
hour or at most one day.) However, an approximate vehicle parasitic current can be measured after 10~20 minutes.
4. Connect an ammeter in series between the battery (-) terminal and the ground cable, and then disconnect the clamp from the battery (-)
terminal slowly.

• Be careful that the lead wires of an ammeter do not come off from the battery (-) terminal and the ground cable to prevent the
battery from being reset. In case the battery is reset, connect the battery cable again, and then start the engine or turn the
ignition switch ON for more than 10 sec. Repeat the procedure from No. 1.To prevent the battery from being reset during the
inspection,
1) Connect a jump cable between the battery (-) terminal and the ground cable.
2) Disconnect the ground cable from the battery (-) terminal.
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3) Connect an ammeter between the battery (-) terminal and the ground cable.
4) After disconnecting the jump cable, read the current value of the ammeter.

5. Read the current value of the ammeter.

A. If the parasitic current is over the limit value, search for abnormal circuit by removing a fuse one by one and checking the parasitic
current.
A. Reconnect the suspected parasitic current draw circuit fuse only and search for suspected unit by removing a component connected
with the circuit one by one until the parasitic draw drops below limit value.
Limit value (after 10~20 min.) :Below 50mA

Cleaning

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1. Make sure the ignition switch and all accessories are in the OFF position.
2. Disconnect the battery cables (negative first).
3. Remove the battery from the vehicle.

Care should be taken in the event the battery case is cracked or leaking, to protect your skin from the electrolyte. Heavy rubber gloves
(not the household type) should be wore when removing the battery.

4. Inspect the battery tray for damage caused by the loss of electrolyte. If acid damage is present, it will be necessary to clean the area with
a solution of clean warm water and baking soda. Scrub the area with a stiff brush and wipe off with a cloth moistened with baking soda
and water.
5. Clean the top of the battery with the same solution as described above.
6. Inspect the battery case and cover for cracks. If cracks are present, the battery must be replaced.
7. Clean the battery posts with a suitable battery post tool.
8. Clean the inside surface of the terminal clamps with a suitable battery cleaning tool. Replace damaged or frayed cables and broken
terminal clamps.
9. Install the battery in the vehicle.
10. Connect the cable terminals to the battery post, making sure tops of the terminals are flush with the tops of the posts.
11. Tighten the terminal nuts securely.
12. Coat all connections with light mineral grease after tightening.

When batteries are being charged, an explosive gas forms beneath the cover of each cell. Do not smoke near batteries being
charged or which have recently been charged. Do not break live circuit at the terminals of batteries being charged.A spark will occur
when the circuit is broken. Keep open flames away from battery.
Vehicle Control System

Troubleshooting
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Vehicle Control System

Description
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Main Features
Main Features Details
Calculates motor torque command with consideration to usable battery power, usable motor
Drive Motor Control
torque, and driver demand (APS, Brake SW, Shift Lever)

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• Calculates motor charge torque command for regenerative braking.
Regenerative Brake Control
• Calculates regenerative brake force.
Sends final FATC allowed power by using the battery information and FATC requested power
A/C Load Control
data.
Determines LDC ON/OFF and operation mode based on the battery information and vehicle
Electric Load Power Supply
status.
Drive Power, Energy Flow, ECO Level, Power Down, Shift Lever Position, Service Lamp &
Cluster Display
Ready Lamp ON Request
• Indicates usable battery energy, and distance to empty based on prior drive pattern.
DTE (Distance to Empty) • If drive path is set by using AVN, DTE accuracy is improved by estimating the energy
consumption to destination.
• Remote control via Center/Smartphone through synchronization with TMU.
Reserve/Remote Charge/A/C
• Reservation function through operation time setting by driver.
Analog/digital signal processing and
APS, Brake Switch, Shift Lever, Airbag Deployment Signal processing and diagnosis
diagnosis

Vehicle Control System

Cruise Control
The cruise control system is engaged by the cruise "ON/OFF" main switch located on right of steering wheel column. The system has the
capability to cruise, coast, accelerate and resume speed.
It also has a safety interrupt, engaged upon depressing brake or shifting select lever.
The ECM is the control module for this system. The main components of cruise control system are mode control switches, transmission
range switch, brake switch, vehicle speed sensor, ECM and ETS motor that connect throttle body.
The ECM contains a low speed limit which will prevent system engagement below a minimum speed of 40km/h (25mph).
The operation of the controller is controlled by mode control switches located on steering wheel.
Transmission range switch and brake switch are provided to disengage the cruise control system. The switches are on brake pedal bracket
and transmission. When the brake pedal is depressed or select lever shifted, the cruise control system is electrically disengaged and the
throttle is returned to the idle position.
Cruise main switch (ON/OFF)
The cruise control system is engaged by pressing the cruise "ON/OFF" main switch. Pressing the cruise "ON/OFF" main switch again
releases throttle, clears cruise memory speed, and puts vehicle in a non-cruise mode.
Set/Coast switch (SET/–)
The "SET/–" switch located on right of steering wheel column has two functions.
The set function - Push the "SET/–" switch and release it at the desired speed. The SET indicator light in the instrument cluster will
illuminate. Release the accelerator pedal. The desired speed will automatically be maintained.
The coast function - Push the "SET/–" switch and hold it when the cruise control is on. The vehicle will gradually slow down. Release the
switch at the desired speed. The desired speed will be maintained.
Push the "SET/–" switch and release it quickly. The cruising speed will decrease by 2.0km/h (1.2mph) or 1.6km/h (1.0mph).
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Resume/Accel switch (RES/+)

The "RES/+" switch located on right of steering wheel column has two functions.
The resume function - If any method other than the cruise “ON/OFF” main switch was used to cancel cruising speed temporarily and the
system is still activated, the most recent set speed will automatically resume when the "RES/+" switch is pushed. It will not resume, however,
if the vehicle speed has dropped below approximately 40km/h (25mph).
The accel function - Push the "RES/+" switch and hold it when the cruise control is on. The vehicle will gradually accelerate. Release the
switch at the desired speed. The desired speed will be maintained.
Push the "RES/+" switch and release it quickly. The cruising speed will increase by 2.0km/h (1.2mph) or 1.6km/h (1.0mph).
Cancel switch (CANCEL)
The cruise control system is temporarily disengaged by pushing the "CANCEL" switch.
Cruise speed canceled by this switch can be recovered by pushing the "RES/+" switch.
Vehicle Control System

System Block Diagram

Component Parts And Function Outline

Component part Function
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Vehicle-speed sensor, ESP/ABS Control Module Converts vehicle speed to pulse.
ECM Receives signals from sensor and control switches.
Cruise control indicator Illuminate when CRUISE main switch is ON (Built into cluster)
Cruise Control switches CRUISE switch Switch for automatic speed control power supply.
Resume/Accel switch (RES +) Controls automatic speed control functions by Resume/Accel switch
Set/Coast switch (RES -) (Set/Coast switch)
Cancel switches Cancel switch Sends cancel signals to ECM.
Brake-pedal switch
Transaxle range switch (A/T)
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ETC Motor Regulates the throttle valve to the set opening by ECM.

* ETC Motor : Electronic Throttle Control Motor

Vehicle Control System

Trouble Symptom Charts

Trouble Symptom 1

Trouble Symptom 2
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Trouble symptom Probable cause Remedy
The set vehicle speed varies greatly upward Repair the vehicle speed sensor system, or
or downward Malfunction of the vehicle speed sensor circuit
replace the part
"Surging" (repeated alternating acceleration
and deceleration) occurs after setting Malfunction of ECM Check input and output signals at ECM

Trouble Symptom 3
Trouble symptom Probable cause Remedy
The CC system is not canceled when the Damaged or disconnected wiring of the brake Repair the harness or replace the brake pedal
brake pedal is depressed pedal switch switch
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Malfunction of the ECM signals Check input and output signals at ECM

Trouble Symptom 4
Trouble symptom Probable cause Remedy
The CC system is not canceled when the shift Damaged or disconnected wiring of inhibitor
switch input circuit Repair the harness or repair or replace the
lever is moved to the "N" position (It is inhibitor switch
canceled, however, when the brake pedal is Improper adjustment of inhibitor switch
depressed) Malfunction of the ECM signals Check input and output signals at ECM

Trouble Symptom 5
Trouble symptom Probable cause Remedy
Temporary damaged or disconnected wiring Repair the harness or replace the "SET/–"
Cannot decelerate (coast) by using the "SET/ of "SET/–" switch input circuit switch
–" switch
Malfunction of the ECM signals Check input and output signals at ECM

Trouble Symptom 6
Trouble symptom Probable cause Remedy
Damaged or disconnected wiring, or short Repair the harness or replace the "RES/+"
Cannot accelerate or resume speed by using circuit, or "RES/+" switch input circuit switch
the "RES/+" switch
Malfunction of the ECM signals Check input and output signals at ECM

Trouble Symptom 7

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Trouble symptom Probable cause Remedy
CC system can be set while driving at a Repair the vehicle speed sensor system, or
vehicle speed of less than 40km/h (25mph), or Malfunction of the vehicle-speed sensor circuit replace the part
there is no automatic cancellation at that
speed Malfunction of the ECM signals Check input and output signals at ECM

Trouble Symptom 8
Trouble symptom Probable cause Remedy
Damaged or disconnected bulb of cruise main
The cruise main switch indicator lamp does switch indicator lamp Repair the harness or replace the part.
not illuminate (But CC system is normal)
Harness damaged or disconnected

Vehicle Control System

Component Location
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1. Audio switch (LH) 3. Bluetooth hands free switch
2. Cruise switch (RH) 4. Trip switch

Vehicle Control System

Circuit Diagram

Vehicle Control System

Removal
1. Disconnect the negative (-) battery terminal.
2. Remove the driver airbag module.
(Refer to the RT group)
3. Remove the steering wheel.
(Refer to the ST group - "Steering column & shaft")
4. Loosen the mounting screws from the rear steering wheel cover.
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5. Separate the upper steering wheel remote control switch (A) from the steering wheel.

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6. Remove the upper steering wheel control switch (B) disconnecting the connector (A).

Installation
1. Install in the reverse order of removal.

Inspection
[Measuring Resistance]
1. Disconnect the cruise control switch connector from the control switch.

2. Measure resistance between terminals on the control switch when each function switch is ON (switch is depressed).
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Resistance
Function switch Terminal
[kΩ ± 5%]
CANCEL 2-4 0.18
SET– 2-4 0.33
RES+ 2-4 0.55
CRUISE 2-4 0.88

3. If not within specification, replace switch.

[Measuring Voltage]
1. Connect the cruise control switch connector to the control switch.

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2. Measure voltage between terminals on the harness side connector when each function switch is ON (switch is depressed).
Function switch Terminal Voltage (V)
CANCEL 2-4 0.63 ~ 0.97
SET– 2-4 1.03 ~ 1.37
RES+ 2-4 1.58 ~ 2.02
CRUISE 2-4 2.08 ~ 2.52

3. If not within specification, replace switch.