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System Description: Notes

  1. FUNCTION OF MAIN COMPONENTS 
    FUNCTION OF MAIN COMPONENTS

    Components Function
    Automatic light control sensor Detects brightness around vehicle and sends information to multiplex network body ECU
    Hazard warning switch On or off state is sent to multiplex network body ECU
    Stop light switch Sends brake pedal state to multiplex network rear ECU
    Engine switch Detects on (IG), on (Ace), off operation.
    Door courtesy switch Detects door open / close state and sends information to multiplex network body ECU
    PNP switch Detects shift position and sends information to ECM
    Swivel motor Moves the headlights laterally according to the information from the AFS ECU, and sends the corresponding information to the AFS ECU.
    Parking brake switch Detects parking brake state and sends information to skid control ECU
    Headlight leveling actuator Moves headlights up and down according to information from AFS ECU
    Headlight leveling actuator Moves headlights up and down according to information from headlight beam level control ECU
    Height control sensor Detects vehicle height and sends corresponding information to AFS ECU
    Height control sensor Detects vehicle height and sends corresponding information to headlight beam level control ECU
    Steering sensor Detects the steering wheel direction and sends the corresponding information to the AFS ECU
  2. OPERATION DESCRIPTION 
    1. Manual lighting system (Front lighting system)
      1. The multiplex network body ECU receives the following:
        • Light switch tail signal
        • Light switch head signal
        • Light switch high beam signal
        • Front fog switch signal
        • Lighting system passing signal
      2. The multiplex network body ECU receives the following:
        • Headlight ON demand signal:

          Sent when light switch head signal is received.

        • Taillight ON demand signal:

          Sent when light switch tail signal and light switch head signal are received.

        • High beam ON signal:

          Sent when light switch high beam signal is received.

        • Front fog light ON signal:

          Sent when light switch tail and front fog switch signals are received.

      3. The engine room NO. 2 junction block receives the ON demand signals from the multiplex network body ECU (see above), and then controls the on/off operation of the following based on the signals:
        • Headlight (low)
        • Headlight (high)
        • Clearance light
        • Front fog light
    2. Manual lighting system (Rear lighting system)
      1. The multiplex network body ECU receives the following:
        • Light switch tail signal
      2. The multiplex network body ECU receives the signal and controls the following:
        • Taillight ON demand signal
        • Rear fog light ON demand signal
      3. The multiplex network rear ECU receives the ON demand signals from the cowl side junction block ECU RH (see above), and then controls the on/off operation of the following based on the signal:
        • Taillight
        • License plate light
    3. Automatic light control system
      1. The multiplex network body ECU receives the following:
        • Light switch auto signal
        • Automatic light control sensor signal
      2. The multiplex network body ECU receives the signals and controls the following:
        • Headlight ON demand signal:

          Sent according to the illumination information from the automatic light control sensor when the light switch auto signal is received.

        • Taillight ON demand signal:

          Sent according to the illumination information from the automatic light control sensor when the light switch auto signal is received.

      3. The engine room NO. 2 junction block receives the ON demand signals from the multiplex network body ECU (see above), and then controls the on/off operation of the following based on the signals:
        • Headlight (low)
        • Clearance light
      4. The multiplex network rear ECU receives the taillight ON demand signal from the cowl side junction block ECU LH, and then controls the on/off operation of the following based on the signal:
        • Taillight
        • License plate light
    4. Turn signal light system
      1. The cowl side junction block ECU LH receives the following:
        • Right turn signal
        • Left turn signal
      2. The cowl side junction block ECU LH receives the signals and controls the following:
        • Right turn ON demand signal

          Sent when the right turn signal is received.

        • Left turn ON demand signal

          Sent when the left turn signal is received.

      3. The turn signal relay receives the ON demand signals from the cowl side junction block ECU LH (see above), and then controls the on / off operation of the following based on the signals:
        • Right turn signal light
        • Left turn signal light
    5. Light auto cut system
      1. The multiplex network body ECU receives the following:
        • Light switch tail signal
        • Light switch head signal
        • Light switch auto signal
        • Front fog switch signal
        • Engine switch signal
        • Automatic light control sensor signal
        • Driver's seat courtesy switch signal
      2. The multiplex network body ECU receives the signals and controls the following:
        • Headlight ON demand signal

          Terminates communication when the engine switch signal terminates and the driver's seat courtesy switch signal is received while sending the headlight ON demand signal. The headlight ON demand signal results from receiving the light switch head signal or the illumination information from the light control signal.

        • Taillight ON demand signal

          Terminates communication when the engine switch signal terminates and the driver's seat courtesy switch signal is received while sending the taillight ON demand signal. The taillight ON demand signal results from receiving the light switch tail signal or illumination information from the light control signal.

      3. The cowl side junction block ECU LH controls the on/off operation of the following:
        • Headlight (low)
        • Headlight (high)
        • Clearance light
        • Front fog light
      4. The multiplex network body ECU receives the taillight and rear fog light ON demand signals, and then controls the on/off operation of the following:
        • Taillight
        • License plate light
    6. Stop light system
      1. The multiplex network rear ECU receives the following:
        • Stop light switch signal
      2. The multiplex network rear ECU receives the signal and controls the following:
        • Stop light ON demand signal
      3. The multiplex network rear ECU controls the on/off operation of the following:
        • Stop light
        • High-mounted stop light
    7. Back-up light system
      1. The multiplex network rear ECU receives the following:
        • Shift position R signal
      2. The multiplex network rear ECU receives the signal and controls the following:
        • Back-up light ON demand signal
      3. The multiplex network rear ECU controls the on/off operation of the following:
        • Back-up light
    8. Illuminated entry system
      1. The multiplex network body ECU receives the following:
        • D/P/RR/RL door courtesy switch signal
        • D/P/RR/RL door lock signal
        • Engine switch signal
      2. The multiplex network body ECU receives the signals and controls the following:
        • Illumination ON demand signal:

          Sent when the respective door courtesy switch signal or door lock signal is received.

      3. The multiplex network body ECU receives the ON demand signal (see above) and controls on/off and fade-in/fade-out operations of the following:
        • Front room light
    9. Rear room light
      1. The multiplex network body ECU receives the following:
        • RR/RL door courtesy switch signal
      2. The multiplex network body ECU receives the signal and controls the following:
        • RR room light ON demand signal

          Sent when the RR door courtesy switch signal is received.

        • RL room light ON demand signal

          Sent when the RL door courtesy switch signal is received.

      3. The cowl side junction block ECU LH receives the ON demand signal (see above) signals and controls the fade-in/fade-out operation of the following:
        • RR seat light
        • RL seat light
    10. Step light system
      1. The multiplex network body ECU receives the following:
        • D/P/RR/RL door courtesy switch signal
        • D/P/RR/RL door lock signal
        • Shift position P signal
        • Engine switch signal
      2. The multiplex network body ECU receives the signals and controls the following:
        • Step light ON demand signal

          Sent when the respective door courtesy SW signal or door lock signal is received or when the shift position P and engine switch signals are received.

      3. The multiplex network body ECU controls on/off/fade-in/fade-out/light control operation of the following based on the ON demand signal (see above):
        • Step light
    11. Door courtesy light lighting system
      1. The multiplex network body ECU receives the following:
        • D/P/RR/RL door courtesy switch signal
      2. Each of the door ECUs receives the respective door courtesy switch signal from the multiplex network body ECU, and then controls the following:
        • Courtesy light ON demand signal:

          Sent when the respective door courtesy switch signal is received.

      3. Each of the door ECUs controls the on/off operation of the following based on the ON demand signal (see above):
        • Courtesy light illumination
    12. Room illumination system
      1. The multiplex network body ECU receives the following:
        • Light switch auto signal
        • Light switch tail signal
        • Light switch head signal
        • Automatic light control sensor signal
      2. The multiplex network body ECU receives the signals and controls the following:
        • Taillight ON demand signal

          Sent when the light switch tail or head signal is received or based on illumination information from the light control signal when the light switch auto signal is received.

      3. The multiplex network body ECU controls the on/off operation of the following based on the ON demand signal (see above):
        • Each room light
        • RR/RL ashtray illumination
    13. Headlight beam level control system
      1. The headlight beam level control ECU receives the following:
        • HEAD relay ON signal
        • Vehicle height sensor signal
        • Vehicle speed signal
        • Generator terminal L signal (the headlight beam level control ECU receives the generator terminal L signal from the ECM via cowl side junction block ECU LH)
      2. The headlight beam level control ECU receives the signals and controls the following:
        • Level control motor operation demand signal: Sent based on the vehicle height sensor signal, passenger side seat occupant signal and vehicle speed sensor when the HEAD relay ON signal is received.
        • Headlight beam level control warning indicator light signal:

          Sent to the combination meter via cowl side junction block ECU LH when the headlight beam level control ECU is malfunctioning.

      3. The headlight beam level control ECU receives the signals and controls the following:
        • Headlight beam level control motor
        • Headlight beam level control warning indicator light
    14. AFS
      1. The AFS ECU receives the following:
        • Headlight ON demand signal
        • Daytime running light ON demand signal
        • Generator L terminal signal
        • Shift position signal
        • Zero point value stored in steering angle sensor
        • Steering angle sensor signal
        • Vehicle height sensor signal
        • Vehicle speed signal
        • AFS OFF switch signal
      2. The AFS ECU receives the signals and controls the following:
        • Leveling actuator operation demand

          Drives based on the vehicle height sensor signal when the headlight ON demand signal or generator L terminal signal is received and the daytime running light ON demand signal is not received.

        • Swivel motor operation demand

          Drives according to the vehicle speed signal and steering angle sensor signal when the headlight ON demand signal, alternator L terminal signal and zero-point value stored in the steering angle sensor are received and the daytime running light ON demand signal, shift position R and N signals, and AFS OFF switch signal are not received.

        • AFS warning signal

          Sent when an abnormality is detected in the respective signal or system.

        • AFS OFF indicator signal

          Sent when the AFS OFF switch is pushed.

    15. The AFS ECU receives the signals and controls the following:
      • Headlight leveling actuator LH
      • Headlight leveling actuator RH
      • Swivel motor LH
      • Swivel motor RH
      • AFS OFF indicator light