Kia Stonic Quiz
Engine Control System/Fuel System

ISG System (Idle Stop & Go)

In this manual: Engine Control System/Fuel System
General Information — 8Maintenance — 31Engine Mechanical — 49Engine Electrical — 15Emission control system — 11Engine Control System/Fuel System — 45Clutch System — 12Manual Transaxle System — 11DCT (Dual Clutch Transmission) System — 16Drive Shafts and Axles — 9Suspension — 16Steering — 10restraint system — 15Braking system — 22Body (Interior and Exterior) — 89Rear Seat — 16Electrical System — 25Electrochromic Interior Rear View Mirror — 64Heating, Ventilation, and Air Conditioning — 31
16steps
~96min
5/5difficulty
Done 0 of 16

Components and Components Location

COMPONENT LOCATION

1. Battery Sensor
2. Brake Booster Vacuum Pressure Sensor (BBVPS)
3. AGM Battery
4. DC-DC Converter [200 W]
5. ISG Switch
6. Generator		 7. Starter
8. Brake Switch
9. Door Switch
10. Child Safety Door Lock Switch
11. Hood Switch

1. Battery Sensor
3. AGM Battery		 2. Brake Booster Vacuum Pressure Sensor (BBVPS)
4. DC-DC Converter [200 W] 5. ISG Switch
6. Alternator 7. Starter
8. Brake Switch 9. Door Switch
10. Child Safety Door Lock Switch 11. Hood Switch

Description and Operation

Description

The Idle Stop & Go (ISG) function automatically stops the engine when the vehicle is stationary and restarts the engine as soon as the brake pedal is released. This reduces not only fuel consumption but also exhaust emissions. The Idle Stop & Go (ISG) function has built-in sensitivity adjustment for safety and driving comfort. The engine does not stop when certain safety and comfort conditions are not met (for example, if the engine oil is still too cold, the battery charge level is too low, or the outside air temperature is below 3 °C). The function is deactivated by pressing the ISG OFF switch on the lower instrument panel. Example situation: the engine stops when you are stopped at a red traffic light or driving in stop-and-go traffic.

HOW IT WORKS

B

Method:

  1. Automatic engine stop function: D range + brake pedal depressed.

  2. Automatic engine restart function

    (1) Brake pedal released.

    (2) Brake pedal depressed + manual shift range (sport mode)

    (3) Brake pedal depressed + reverse range

  3. Vehicle is moving.

  4. Shift lever is in D. Brake pedal is not depressed.

  5. Engine is running (vehicle is moving).

  6. Driver brakes until the vehicle comes to a complete stop.

  7. Shift lever is in D. Brake pedal is depressed.

  8. Engine stops. The "AUTO STOP" indicator illuminates on the instrument cluster.

  9. The driver wants to continue driving.

8th.

Shift lever is in D. Brake pedal is not depressed.

  1. The engine restarts. The "AUTO STOP" indicator turns off.

or

  1. Vehicle is moving.

  2. gear is engaged. Accelerator pedal is depressed.

  3. Engine running.

  4. Driver brakes until the vehicle comes to a complete stop.

  5. The driver shifts into neutral and releases the clutch pedal.

  6. Engine stops. The "AUTO STOP" indicator illuminates on the instrument cluster.

  7. The driver wants to continue driving.

8th.

The driver depresses the clutch pedal. The engine starts.

  1. The shift lever can be moved to a driving position and the vehicle can continue. The "AUTO STOP" indicator turns off.

Schematic diagrams

ISG Function Activation Conditions (A)

1. Auto Stop or Auto Restart Status

▶ When all of the following conditions are met

COMPONENTS LOCATION Condition NOTICE
ISG OFF Outside ISG OFF Switch Indicator -> OFF
Climate Control System Outside air temperature from -2 to 35 °C
Engine Coolant Temperature Above 30 °C
Brake Vacuum Below -35 kPa
Driver's Door, Seat Belt, Hood Closed
Emergency Vehicle Status
(TPS/CKP/CMP/WTS/Vehicle Speed Signal)		 Operation DPF regeneration prohibited
Air Conditioner Operation
Battery sensor
[SOC: above 78% Temperature: 2 ~ 55 °C]		 Operation
ISG-Related Part Malfunction Not Applicable
Vehicle speed Input less than 0 km/h after more than 8 km/h ISG System Locked below 8 km/h
ACCELERATOR Outside Automatic Engine Stop Function
Brake Switch A Automatic Engine Stop Function
Outside Automatic Engine Stop Function
Band Status N (Neutral) / D Automatic Engine Stop Function
P / 1 / 2 Automatic Engine Stop Function

2. Restriction Conditions for Auto Stop or Auto Restart

▶ When any of the following conditions are met, the ISG system does not operate properly.

COMPONENTS LOCATION Conditions NOTICE
ISG switch A ISG OFF Switch Indicator Status
Emergency Service Status
(TPS/CKP/CMP/WTS/vehicle speed signal, etc.)		 Dissatisfaction DPF regeneration prohibited
Driver's door, seat belt, hood status Open
Brake Vacuum Above -35 kPa
A/C status Dissatisfaction
Battery sensor
(SOC: above 78%, temperature: 2 ~ 60 °C)		 Dissatisfaction
ISG system error Occurs
steering wheel The greater the angle
Air Conditioner A/C ON, FATC above 6, MTC above 3
DEF Defrost switch ON
etc. Downhill slopes, rapid uphill climbs
Activate EPS

3. Forced Restart Conditions (if any of the following conditions are not met)
COMPONENTS LOCATION Conditions NOTICE
Safety conditions Low brake system pressure Above -35 kPa
Low Battery Voltage Maintain electrical load for 3 minutes
Active windshield defroster
When inertia speed reaches 1.5 km/h
Open the door or unfasten the driver's seat belt Brake pedal depressed
Open the hood, start the engine
Stop time too long After 300 s
Vehicle stopped on a steep downhill
Comfort conditions A/C ON, FATC above 6, MTC above 3, or HVAC performance unsatisfactory
ISG OFF button active

4. Restricted Conditions for Auto Stop Operation

Conditions Condition NOTICE
Driver's door, seat belt, hood status (brake not applied) Open Starting is possible only with the "ignition switch or engine start button"
CAN error (TCU, FATC/instrument cluster) Occurs
EMS status (TPS/CKP/CMP/WTS/vehicle speed signal) Dissatisfaction

ISG Function Activation Conditions (M/T)

After each engine start, the function is automatically activated and enters standby mode. The ISG OFF switch can be used to manually deactivate this function until the next start. Turn the ignition off. When the switch is pressed, the indicator light illuminates.

1. Idle stop condition (Idle → Stop)

▶ General condition: Neutral position and clutch pedal released

Prerequisites
Engine coolant temperature is not too low (above 45 °C).
No DPF regeneration
No interlock conditions for activation or engine failure

  • CKPS, CMPS, ECTS, VSS, battery sensor, BBVPS, neutral switch, clutch switch, APS, injector
Battery charge level is sufficiently high.
No fault in communication line - LIN, CAN
Vehicle speed below 5 km/h
Vehicle speed above 10 km/h at least once after key-on or from standby mode
ISG OFF switch OFF
Driver seat belt, driver door and hood are closed.
Battery temperature from 2 to 55 °C.
Brake booster pressure is not too low.
Fan not at maximum.

2. Idle Stop Restart Conditions (Stop → Start)

▶ General condition: Neutral position and clutch pedal depressed

Prerequisites
No interlock conditions for activation or engine failure

  • CKPS, CMPS, ECTS, VSS, battery sensor, neutral switch, clutch switch, APS
No fault in communication line - LIN, CAN
Driver seat belt and driver door or hood are closed.
Engine off, then gear shift (in gear → neutral) and clutch pedal operated.

3. Auto start condition (Stop → Start)

The engine starts automatically without driver intervention in the following cases:

▶ General condition: Neutral position and clutch pedal released

Prerequisites
No interlock condition for activation

  • TPS, CKPS, CMPS, ECTS, VSS, battery sensor, BBVPS, neutral switch, clutch switch
Brake booster vacuum sensor value too low.
When the battery charge level is too low.
After a certain period of time has elapsed following A/C activation.
Vehicle speed above 5 km/h when descending a hill.
Fan at maximum.

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