System Description

GENERAL
1. This system uses ultrasonic sensors to detect any obstacles at the front and rear of the vehicle. The system then informs the driver of the distance between the sensors and the obstacles as well as their positions by indicating them on the multi-display or multi-information display and by sounding a buzzer.

FUNCTION OF COMPONENTS

FUNCTION CHART

Components	Function
Ultrasonic sensors	Detects distance between vehicle and obstacle
Clearance sonar main switch	Outputs system ON/OFF signals to clearance warning ECU1 or parking assist ECU2 via CAN
Clearance warning buzzer	Sounds buzzer to inform driver according to distance to obstacle.
Clearance warning ECU1 Parking assist ECU2	Receives signals from various systems and determines system operation condition Amplifies and processes sent and received ultrasonic waves, makes judgments about obstacles, controls indicator light and warning buzzer, and detects sensor malfunctions
Combination meter (Multi-information display)	Transmits vehicle speed signal to clearance warning ECU1 or parking assist ECU2. Displays location of obstacle and approximate distance between vehicle and obstacle. Informs driver if ultrasonic sensors malfunction, or if they freeze or become dirty.
Steering control ECU	Outputs variable gear ratio steering signal (in either steering direction) to clearance warning ECU1 or parking assist ECU2 via CAN
Multi-display1 Display and Navigation Assembly2	Receives information from clearance warning ECU1 or parking assist ECU2 through CAN and AVC-LAN, and then displays detection information
Park/Neutral position switch	Outputs shift lever position signal (system operation condition) to ECM
ECM	Transmits shift position signal to clearance warning ECU1 or parking assist ECU2
Air Conditioning Amplifier	Transmits ambient temperature to clearance warning ECU1 or parking assist ECU2
Outer mirror switch	Transmits clearance sonar main switch signal to clearance warning ECU1 or parking assist ECU2
Main body ECU	Transmits destination symbol and steering wheel symbol to clearance warning ECU1 or parking assist ECU2
Front controller	Transmits wiper status signal to clearance warning ECU1 or parking assist ECU2
HINT: 1: w/o Advanced parking guidance system 2: w/ Advanced parking guidance system

OPERATION EXPLANATION
1. The ECU determines whether the intuitive parking assist system should be operated based on the clearance sonar main switch ON/OFF status, the shift position and the vehicle speed.
2. When the system operates, the ECU transmits ultrasonic waves from the ultrasonic sensors. If these waves encounter an obstacle within one or more of the sensors' ranges, the waves are reflected back to the sensors, which transmit them to the ECU. Based on this information, the ECU sends signals to the multi-information display, the multi-display and the clearance warning buzzer. The approximate distance between the vehicle and the obstacle is then indicated, and the buzzer sounds.
  HINT:
  
  Refer to "OPERATION CHECK" for the detailed operation (see OPERATION CHECK ).
ECU OR SENSORS WHICH COMMUNICATE THROUGH SENSOR COMMUNICATION
HINT:
- The ECU and sensors communicate with each other using sensor communication.
- Allocation refers to the process of the ECU setting aside IDs for the sensors.
- The vehicle has the sensors arranged in 2 groups*1 or 3 groups*2. There is a front series and a rear series. The sensors are connected in a "daisy chain".
HINT:

*1: w/o Advanced parking guidance system

*2: w/ Advanced parking guidance system
1. Initialization mode:
  An ID is allocated to each sensor and sensor diagnosis is performed.
  
  HINT:
  
  *1: w/o Advanced parking guidance system
  
  *2: w/ Advanced parking guidance system
  1. When any of the following conditions are met, the ECU provides power to the first sensors in each series (front left side sensor* 1, front left corner sensor*2 and rear right corner sensor):
    - The engine switch is turned on (IG).
    - The sensor operating conditions (described previously) are met and the clearance sonar main switch is turned ON.
    - Vehicle speed is below 9 km/h (5.6 mph).
  2. After power is supplied, front left side sensor and rear right sensor enter standby mode to receive an ID from the ECU. When a certain amount of time has elapsed, the ECU sends an ID allocation signal to these sensors.
  3. The front left side sensor and rear right sensor receive the ID allocation signal from the ECU and perform self-diagnosis. When the sensor self-diagnosis is complete, the ECU sends an ID allocation confirmation signal to the sensors.
  4. After the ID allocation confirmation is performed, the ECU provides power to the second sensors in each series (front left corner sensor*1, front left center sensor*2 and rear right center sensor) via the first sensors. In the same manner as the first sensors, the second sensors enter the standby mode. When a certain amount of time has elapsed, the ECU sends an ID allocation signal to the second sensors.
  5. The above operation will be repeated until an ID is allocated to the last sensor, which is in the rear series (rear left sensor). Initialization ends when ID allocation to all ultrasonic sensors is complete.
2. Detection mode:
  After the initialization mode is complete, the system switches into the detection mode. In the detection mode, the ECU sends information request signals and sensor activation signals to the ultrasonic sensors and receives detection result signals from the sensors.
  1. The ECU regularly sends ID signals, information request signals, and sensor activation signals to an ultrasonic sensor according to the sensor communication schedule.
  2. When a certain amount of time has elapsed (sensor detection operation is complete), the ECU sends an ID signal to the sensor to receive a detection result signal.
  3. The ultrasonic sensor sends a detection result signal or detection information signal to the ECU.
  4. The above operation is repeatedly performed for each ultrasonic sensor.