Function, structure, operation of body control (eCall unit)

1. Emergency call system overview

The Emergency Call System (eCall System) is a system that makes an emergency call using the Global Navigation Satellite System (GNSS). The eCall System is activated when the airbag is deployed or when the SOS button is pressed. When the eCall System is activated, an emergency call is made to the emergency call center, and at the same time, the vehicle location, vehicle identification number, etc., are sent. After that, a voice call is started with the operator of the emergency call center, and if there is no response from the occupant, the operator immediately dispatches an emergency service for rescue.

Note

  • Do not press the SOS button except in an emergency. If the SOS button is accidentally pressed, tell the operator about the situation by a voice call.
  • If the emergency call system does not operate normally, request for a rescue using a public telephone, etc., around the vehicle.

Diagram of input/output

2. Emergency call system

1. System activation

When the ignition switch is turned ON, the indicator light illuminates in red for 3 to 4 seconds, illuminates in green for approximately 4 seconds, and then turns OFF. If there is a malfunction in the system, the indicator light remains illuminating in red.

Legend

  1. SOS button
  2. Indicator light

2. System operation

The emergency call system is activated when the airbag is deployed or when the SOS button is pressed for 1 second or more. When the emergency call system is activated, the audio is automatically muted so that the voice call between the operator of the emergency call center and the occupant is not interrupted.

Note

  • When connected to the operator of the emergency call center, the voice call cannot be canceled from the vehicle.

Emergency call system operation diagram

1) Emergency call

It is sent to the emergency call center when the airbag is deployed or the SOS button is pressed.

2) Identification of location

Vehicle information such as the occurrence location, vehicle traveling direction, vehicle model, and number of occupants is sent to the emergency call center.

3) Information acquisition

A voice call between the emergency call center operator and the occupant starts. If there is no response from the occupant, the operator immediately dispatches an emergency service for rescue.

3. Indicator light/alarm

Depending on the operating state of the emergency call system, the illumination/flashing state and lighting color of the indicator light are different. An alarm also sounds depending on the situation.

Condition
Color
(Red/Green)
Illuminated or flashing
Alarm sound
During initial diagnosis (Ignition switch is turned ON)
Red (3 to 4 seconds)
Green (approx. 4 seconds)
Illuminated
-
During emergency call
Green
Flashing
-
When voice call starts
Green
Illuminated
One continuous beep
During voice call
Green
Illuminated
-
Emergency call connection failure
Red
Flashing
A series of short beep with pauses
When the battery built into eCall unit needs to be replaced
Red
Illuminated
A series of long beeps
When the contract of the SIM built into eCall unit will expire in less than 6 months.
Red
Illuminated
A series of long beeps
When system malfunctions
Red
Illuminated
A series of long beeps

3. Emergency call system components

1. eCall unit

The eCall unit is installed in the center of the instrument panel. The eCall unit activates the emergency call system when the airbag is deployed or when the SOS button is pressed. When the system is activated, the battery built into the eCall unit is used. In addition, the eCall unit has a self-diagnosis function. If a malfunction occurs in the system, the indicator light (red) is illuminated and an alarm sounds from the speaker.

2. SOS button / Indicator light

The SOS button is integrated with the indicator light and is installed to the overhead console. The emergency call system is activated automatically only when the airbag is deployed. In an emergency such as a traffic accident and sudden illness, the emergency call system can be activated manually by pressing the SOS button for 1 second or more.
The indicator light flashes in green during an emergency call and illuminates in green during a voice call. Also, if the battery built into the eCall unit needs to be replaced or if there is a malfunction in the system, the indicator light remains illuminating in red.

Legend

  1. SOS button
  2. Indicator light

Note

  • The SOS button itself illuminates when the light control switch is in the taillight position, AUTO position (night-time only) or headlight position.

3. Antenna

The GNSS antenna and TEL antenna are integrated into an antenna, and the antenna is installed in the center of the instrument panel. The GNSS antenna receives GNSS signals, and the TEL antenna transmits emergency calls to the emergency call center when the emergency call system is activated.

4. Speaker microphone

The microphone and speaker are integrated into the speaker microphone, which is installed in the overhead console. When the emergency call system is activated, a voice call can be made between the emergency call center operator and the occupant via the speaker microphone. If there is no response from the occupant, the operator immediately dispatches an emergency service for rescue. Also, if there is a malfunction in the system, an alarm sounds from the speaker.

Note

  • The volume of the microphone and speaker cannot be adjusted.

5. ECM

The ECM sends vehicle speed signals to the eCall unit via the CAN communication circuit.

6. SRS control unit

The SRS control unit sends deployment signals to the eCall unit via the deployment signal circuit. The deployment signals are sent from the SRS control unit to the eCall unit via CAN communication as well.

7. BCM

The BCM sends the hazard warning flasher switch and turn signal switch signals to the eCall unit via the CAN communication circuit.

8. Instrument panel cluster

The instrument panel cluster sends seat belt switch signals to the eCall unit via the CAN communication circuit.

9. Audio

When the audio receives the mute signals from the eCall unit via the MUTE output circuit while the emergency call system is operating, the audio stops the sound output.

4. Emergency call system component views

Legend

  1. Antenna
  2. eCall unit

Legend

  1. Speaker microphone
  2. SOS button

5. General circuit diagram

1. eCall unit general circuit diagram

2. eCall unit outline view and connector face

Pin No.
Pin function
1
Indicator light (red) control
2
Indicator light (green) control
3
Speaker microphone power supply
4
Speaker microphone input (+)
5
Speaker microphone input (-)
6
Speaker microphone output (+)
7
Speaker microphone output (-)
8
Ground
9
CAN (High)
10
CAN (Low)
11
Ground
12
UART communication
13
UART communication
14
Air bag active PWM signal
15
-
16
Ignition power supply
17
SOS button signal
18
SOS button / Indicator light ground
19
-
20
-
21
Speaker microphone ground
22
Speaker output (-)
23
Speaker output (+)
24
-
25
Ground
26
Ground
27
-
28
Mute control
29
-
30
Accessory power supply
31
-
32
Battery power supply