CAN COMMUNICATION SYSTEM FAIL-SAFE CHART


  1. FAIL-SAFE FUNCTION


    1. When communication fails in any of the CAN bus wires (communication wires) due to a short circuit or other causes, the fail-safe function, which is specified for each system, operates to prevent the system from malfunctioning.

    2. The following chart shows the relationships between components, system functions, and effects of communication failure on these functions. (For further details, see the procedures for each system.)

      Function

      (Function Description)

      		 Control Master Related System Fail-safe Operation

      DTC

      (Driver Detectable)

      ABS control

      (Control driving force while ABS in operation)

      		 Skid Control ECU Yaw Rate Sensor

      Control inoperative

      (gradually stops controlling during ABS control)

      U0073, U0123, U0124

      (Warning light comes on)

      TRC control

      (Engine power control by VSC/TRC)

      VSC control

      (Controls driving force while VSC in operation)

      		 Skid Control ECU

      • ECM

      • Steering Sensor

      • Yaw Rate Sensor

      TRC control is inoperative

      (TRC control gradually stops)

      VSC control is inoperative

      (VSC control gradually stops)

      U0073, U0100, U0123, U0124, U0126

      (Warning Light comes on)

      Electric power steering

      (Speed of vehicle induction type torque control)

      		 Power Steering ECU

      • ECM

      • Skid Control ECU

      • Engine Stop and Start ECU*4

      		 Steering assist force is maintained at the level for about 100 km/h (62 mph).

      U0100, U0129, U1103

      (Warning Light comes on)
      Air Conditioner Control Air Conditioning Amplifier Assembly

      • ECM

      • Power Steering ECU

      • Combination Meter ECU

      • Main Body ECU

      • Engine Stop and Start ECU*4

      		 Air conditioning function stops

      U0100, U0131, U0142, U0155

      (Air conditioning inoperative)

      Event Recorder

      (Tracks event data such as vehicle speed and accelerator opening angle and records data)

      		 Center Airbag Sensor Assembly

      • ECM

      • Combination Meter ECU

      • Main Body ECU

      		 Data not recorded None
      Meter display (Vehicle status display and indicator light control) Combination Meter ECU

      • ECM

      • Skid Control ECU

      • Power Steering ECU

      • Center Airbag Sensor Assembly

      • Power Management Control ECU*1

      • Power Source Control ECU*2

      • Main Body ECU

      • Certification ECU*3

      • Engine Stop and Start ECU*4

      		 Light does not come on, illuminates abnormally, or blinks abnormally

      U0100, U0129, U0131, U0151

      (Abnormal light illumination)
      Buzzer Control Combination Meter ECU

      • Skid Control ECU

      • Air Conditioning Amplifier Assembly

      • Main Body ECU

      • Certification ECU*3

      		 Buzzer function stops

      U0129

      (Buzzer does not sound)
      Push Start

      Power Management Control ECU*1

      Power Source Control ECU*2

      • ECM

      • Combination Meter ECU

      • Main Body ECU

      • Certification ECU*3

      		 The message "Depress brake pedal and push engine switch to start" is not displayed when necessary.

      U0100, U1133,

      (Same as shown to the left)

      Watch Sub Bus

      (Power Management Bus)

      		 Power Management Control ECU*1

      • ECM

      • Air Conditioning Amplifier Assembly

      		 -

      U0100, U1002

      (None)
      Key Lock-in Prevention Main Body ECU Combination Meter ECU Key lock-in prevention function inoperative

      None

      (Control is inoperative)
      Smart/Wireless Control Main Body ECU

      • Combination Meter ECU

      • Certification ECU*3

      		 Entry lock/unlock not possible

      U0142, U0155, U0327

      (Control is inoperative)
      Illumination Control Main Body ECU

      • Combination Meter ECU

      • Certification ECU*3

      		 Illumination control not possible

      U0142, U0327

      (Dome light will not come on)
      Back Door Open Control Main Body ECU

      • Combination Meter ECU

      • Certification ECU*3

      		 Power back door open function inoperative

      U0142, U0155, U0327

      (Control is inoperative)
      Stop and Start System*4 Engine Stop and Start ECU

      • ECM

      • Skid Control ECU

      • Power Steering ECU

      • Center Airbag Sensor Assembly

      • Combination Meter ECU

      • Main Body ECU

      • Air Conditioning Amplifier Assembly

      		 Idling stop control stopping

      U0100, U0121, U0131, U0140, U0151, U0164

      (Warning Light comes on)

      *1: for 1KR-FE and 1NR-FE with Entry and Start System

      *2: for 1ND-TV with Entry and Start System

      *3: w/ Entry and Start System

      *4: w/ Stop and Start System