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 pages for each system.)

      Function

      (Function Description)

      		 Control Master System Related Fail-safe Operation

      DTC

      (Driver Detectable)

      VSC control

      (Controls driving force while VSC in operation)

      		 Skid Control ECU

      • ECM

      • Steering Angle Sensor

      • Yaw Rate Sensor

      VSC control is inoperative

      (VSC control gradually stops)

      U0073, U0100, U0123, U0124, U0126

      (Warning light comes on)

      VSC control

      (Engine power control by VSC/TRC)

      		 Skid Control ECU

      • ECM

      • Steering Angle Sensor

      • Yaw Rate Sensor

      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

      Depression of EPS assist

      (Deterioration of steering)

      U0100, U0129

      (VSC failure: warning light comes on, and decrease of assistance power at vehicle speed 120 km/h [74mph])

      (ECM failure : Warning light comes on [only before assist beginning])
      Meter display (Displays operation condition and DTCs) Combination Meter

      • ECM

      • Skid Control ECU

      • Center Airbag Sensor Assembly

      • Certification ECU

      • Main Body ECU

      • Power steering ECU

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

      U0100, U0129

      (Abnormal light illuminates)
      Meter buzzer (Combination meter) Combination Meter

      • ECM

      • Skid Control ECU

      • Center Airbag Sensor Assembly

      • Certification ECU

      • Main Body ECU

      		 Meter buzzer does not ring U0100, U0129
      Air conditioning control Air Conditioning Amplifier

      • ECM

      • Combination Meter

      • Main Body ECU

      		 Air conditioning function and PTC heater function stop

      B1499

      (Air Conditioning is inoperative)

      Smart entry function/Power door lock control*1

      		Main Body ECU

      • Certification ECU

      • Combination Meter

      • Back Door ECU

      		 Unlock permitted

      U0230, U0327, U1002

      (Wireless door lock cannot operate)

      *1: w/ Smart entry and start system