CAN COMMUNICATION SYSTEM FAIL-SAFE CHART


  1. FAIL-SAFE FUNCTION


    1. When communication fails in any of the CAN bus wires (communication wires), a fail-safe function(s) will operate. The fail-safe function that is specified for each system operates to prevent those systems from malfunctioning.

    2. The following table shows the effects on each system when communication is impossible. (For further details, see the pages for each system.)

      Function

      (Function Description)

      		 Control Master System Related Fail-safe Operation

      DTC

      (Driver Detectable)

      Power switch

      (Power source control)

      		 Power management control ECU

      • Transmission control ECU assembly

      • Skid control ECU (Brake booster with master cylinder assembly)

      • Main body ECU

      • Power switch does not change to on (READY) even when power switch is pressed with the brake pedal depressed

      • Power switch off is prohibited

      U0073

      U0129

      U0293

      (Warning and indicator lights come on)
      Hybrid driving control Power management control ECU ECM Only motor operation is used (Engine is not used)

      U0100

      (Warning and indicator lights come on)
      Shift position indicator display (P indicator only) Transmission control ECU assembly

      • Power management control ECU

      • Main body ECU

      • Combination meter assembly

      		 Shift position indicator is not displayed

      U0146

      (Warning and indicator lights come on)
      Regenerative braking control Skid control ECU Power management control ECU

      Regenerative braking will stop

      (ABS/VSC control gradually stops)

      U0073

      U0129

      U0293

      (Warning and indicator lights come on)

      VSC control

      (Controls driving force while VSC operating)

      		 Skid control ECU (Brake booster with master cylinder assembly)

      • Power management control ECU

      • Yaw rate and acceleration sensor

      • Steering angle sensor

      ABS/VSC control is inoperative

      (ABS/VSC control gradually stops)

      U0073

      U0123

      U0124

      U0126

      U0293

      (Warning and indicator lights come on)

      ABS control

      (Controls driving force while ABS operating)

      		 Skid control ECU (Brake booster with master cylinder assembly) Yaw rate and acceleration sensor

      ABS control is inoperative

      (ABS control gradually stops)

      U0073

      U0123

      U0124

      (Warning and indicator lights come on)

      TRC control

      (Engine power control by VSC/TRC)

      		 Skid control ECU (Brake booster with master cylinder assembly)

      • Power management control ECU

      • Yaw rate and acceleration sensor

      • Steering angle sensor

      ABS/VSC control is inoperative

      (ABS/VSC control gradually stops)

      U0073

      U0123

      U0124

      U0126

      U0293

      (Warning and indicator lights come on)

      Electric power steering control

      (Speed of vehicle induction type torque control)

      		 Power steering ECU

      • Power management control ECU

      • Skid control ECU (Brake booster with master cylinder assembly)

      Depression of EPS assist

      (Deterioration of steering assist)

      U0129

      U0293

      (Warning light comes on)

      Air conditioning control

      (Air conditioning control is in cabin)

      		 Air conditioning amplifier assembly

      • Power management control ECU

      • ECM

      • Combination meter assembly

      • Main body ECU

      		 Air conditioning function and PTC heater function stop

      U0100

      U0142

      U0155

      U0293

      (Air conditioning is inoperative)
      Entry function/Power door lock control

      • Certification ECU

      • Main Body ECU

      • ECM

      • Combination meter assembly

      • Power management control ECU

      		 Unlock permitted

      U0100

      U0142

      U0155

      U0293

      U0327

      (Wireless door lock cannot operate)
      Multi-information display Combination meter assembly Power management control ECU

      Display becomes black

      (only measurement units are displayed)

      -

      (none)