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. 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)
      Electric fan (Controlled by a request from air conditioning system) ECM Air conditioning amplifier Fans operate continuously -
      Power management control ECU (Cooperative control between power management control ECU and engine) Power management control ECU - Engine stop

      U0293

      (Warning and indicator lights come on)
      VDIM Control (Controls driving force while VDIM is operating) Skid control ECU

      • Power management control ECU

      • Steering angle sensor

      • Yaw rate sensor

      • Skid control ECU

      		 VDIM functions are prohibited

      U0123

      U0124

      U0126

      U0293

      (Warning and indicator lights come on)
      Regenerative Braking (Motor acts as a generator, charging HV battery using force from rotation of the wheels) Skid control ECU

      • Power management control ECU

      • Skid control ECU

      		 Regenerative braking is prohibited

      U0129

      (Warning and indicator lights come on)
      Electric power steering control (Assist output current) Power steering ECU

      • Skid control ECU

      • Center airbag sensor assembly

      		 Control continues with steering assist force based on a vehicle speed of approximately 100 km/h (62.2 mph)

      U0129

      (Warning lights come on)
      Torque steer control (Controls turning of steering wheel due to a difference in rigidity between left and right drive shafts) Power steering ECU Power management control ECU Amount of control determined by torque steer control becomes 0 -
      Sport mode (Steering feel changes when SPORT mode is selected using DISP switch on steering wheel) Power steering ECU Power management control ECU Control continues using assist map selected before communication interruption occurred -
      Entry and start function/Power door lock control

      • Certification ECU

      • Main body ECU

      • Certification ECU

      • Main body ECU

      		 Doors cannot be unlocked or locked using entry and start/wireless function -
      Coolant temperature gauge (Combination meter) Combination meter ECM Lower than middle on coolant temperature gauge U0100
      Speedometer display (Combination meter) Combination meter Skid control ECU Speedometer displays 0 km/h (0 mph) U0129
      Hybrid system indicator (Combination meter) Combination meter Power management control ECU Hybrid system indicator position is maintained as it was before interruption -
      Energy monitor display (Multi-information display) Combination meter Power management control ECU Display becomes black (only measurement units are displayed) -
      Fuel consumption display (Displays graph of fuel consumption per minute and history of total fuel consumption)

      • Combination meter

      • Multi-media module receiver assembly

      • Radio receiver assembly

      • Combination meter

      • Power management control ECU

      • Skid control ECU

      		 If a communication interruption occurs, values are not displayed

      U0073

      U0100

      U0129

      U0155

      U0293
      Air conditioning (Shows air conditioning settings on multi-display and sends information about function operated through display to air conditioning amplifier)

      • Air conditioning amplifier

      • Radio receiver assembly

      		 Air conditioning amplifier Air conditioning system indicators turn off. If set temperature is shown on multi-information display or multi-display, set temperature display turns off U0073
      Air conditioning control (Controls air conditioning functions such as set temperature adjustment, air outlet selection, etc. using multi-media module receiver assembly or radio receiver assembly)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      		 Air conditioning amplifier

      • When set temperature is shown on multi-display, set temperature display turns off

      • Air conditioning function(s) are prohibited

      • A message indicating to check air conditioning amplifier connection appears on multi-display

      		 U0073
      Intuitive parking assist setting/Notification (Sets display on/off using multi-media module receiver assembly or radio receiver assembly, displays clearance sonar status and sounds buzzer)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      • Clearance warning ECU

      • Radio receiver assembly

      • If a communication interruption occurs while intuitive parking assist setting screen is displayed on multi-display, setting screen turns off

      • If a communication interruption occurs while intuitive parking assist status screen is displayed on multi-display, status screen turns off

      • "LEXUS Park Assist" icon on vehicle settings screen displayed on multi-display turns off

      U0073

      U0100

      U1110
      Driving range display (Multi display)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      • Combination meter

      • Skid control ECU

      • Power management control ECU

      • ECM

      Display updating is stopped

      Values for driving range are cleared

      U0100

      U0129

      U0155

      U0293
      Energy monitor display (Multi display)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      		 Power management control ECU Display updating is stopped U0293
      Vehicle information (Reads CAN data and changes radio receiver assembly settings)

      • Radio receiver assembly

      • Main body ECU

      • Power management control ECU

      • Main body ECU

      • Latest information is used for judgment

      • If a communication interruption is detected while camera screen is displayed (during ON judgment), camera image is not displayed

      U0073

      U0140

      U0293
      Vehicle customize function (Collects data from ECUs with customizable functions and sends setting change information)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      • Main body ECU

      • Clearance warning ECU

      • Main body ECU

      • Air conditioning amplifier

      • Front power seat switch

      		 If a normal response is not received after performing "support information reading process" twice, a processing error DTC is stored for respective ECU

      U0073

      U0140
      Parking assist monitor system control (Displays parking assist monitor based on signals from steering angle sensor, vehicle speed sensor, etc) Multi-media module receiver assembly

      • Skid control ECU

      • Power management control ECU

      • Steering angle sensor

      • If a communication interruption occurs while predicted path guide lines are displayed, guide lines disappear and a message indicating that guide lines cannot be displayed appears on bottom of screen

      • If a communication interruption occurs while vehicle is in parallel parking guide mode, a message indicating that guidance is not available appears on bottom of screen

      U0126

      U0140

      U0293
      Parking assist monitor system

      • Navigation ECU

      • Parking assist ECU

      • Main body ECU

      • Skid control ECU

      • Power management control ECU

      • ECM

      • Steering angle sensor

      		 Parking guide lines are not displayed

      U0100

      U0293

      U0126

      U0142

      (Inoperative message is displayed)
      Power back door control Main body ECU

      • Power back door ECU

      • Main body ECU

      • Combination meter

      		 Power back door function is prohibited U0230
      Headlight swivel/leveling control (Headlight control) AFS ECU

      • Main body ECU

      • Skid control ECU

      • Power management control ECU

      • Steering angle sensor

      		 Swivel and/or leveling control is prohibited

      U0293

      U0129

      U0142

      U0126

      U0101

      (Indicator lights come on)
      Dynamic radar cruise control (Maintains vehicle-to-vehicle distance) Driving support ECU

      • Seat belt control ECU

      • Main body ECU

      • Combination meter

      • Skid control ECU

      • Power management control ECU

      • ECM

      • Steering angle sensor

      • Yaw rate sensor

      		 Vehicle-to-vehicle distance control is prohibited

      U1104

      U0122

      U0123

      U0126

      U0293

      U1100

      (Warning and indicator lights come on)
      Side monitor function Parking assist ECU

      • Main body ECU

      • Skid control ECU

      • Power management control ECU

      • ECM

      • Steering angle sensor

      		 Side monitor is not displayed

      U0073

      U0100

      U0293

      U0126

      U0142

      U0129

      (Inoperative message is displayed)
      LEXUS parking assist-sensor function (Provides notification when an obstacle is detected)

      • Parking assist ECU

      • Clearance warning ECU

      • Main body ECU

      • Navigation ECU

      • Combination meter

      • ECM

      • Air conditioning amplifier

      		 LEXUS parking assist-sensor function is prohibited

      U0101

      U0155

      U0142
      Intuitive parking assist system (Displays LEXUS park assist settings on multi-display, sends information about functions operated through screen to sonar and displays information received from sonar on screen)

      • Multi-media module receiver assembly

      • Radio receiver assembly

      • Clearance warning ECU

      • Certification ECU

      • Clearance warning ECU

      		 If a communication interruption occurs while settings screen is displayed, settings screen turns off ("LEXUS Park Assist" icon on vehicle settings screen also turns off)

      U0073

      U0100

      U1110
      Air suspension control Suspension control ECU

      • Driving support ECU

      • AFS ECU

      • Main body ECU

      • Navigation ECU

      • Yaw rate sensor

      • Skid control ECU

      • Power management control ECU

      • ECM

      • Suspension control ECU

      Height control is set to "normal mode"

      Luggage mode is prohibited

      U0073

      U0100

      U0101

      U0122

      U0124

      U0293

      U0140

      (Warning light comes on)
      Pre-crash safety control (Requests braking and seat belt tightening when an unavoidable collision possibility is detected) Seat belt control ECU

      • Driving support ECU

      • Center airbag sensor assembly

      • Skid control ECU

      • Seat belt control ECU

      • Main body ECU

      		 Pre-crash safety control is prohibited

      U0122

      U0140

      U0151

      U1104

      (Indicator light comes on)
      Power tilt and power telescopic steering column control Tilt and telescopic ECU

      • Front power seat switch

      • Main body ECU

      • Combination meter

      Driving position memory function is prohibited

      Auto away/return function is prohibited

      -

      (Indicator light comes on)
      Air conditioning control Air conditioning amplifier

      • Main body ECU

      • Navigation ECU

      • Combination meter

      • ECM

      • Power management control ECU

      		 Air conditioning function(s) are prohibited

      U0100

      U0101

      U0293

      U0131

      U0142

      U0155
      Air conditioning control (A/C ECU and A/C inverter signal transmission) Air conditioning amplifier - Normal driving U0164
      Seat position memory Front power seat switch

      • Tilt and telescopic ECU

      • Main body ECU

      • Combination meter

      Auto memory recall is prohibited

      Memory is prohibited

      		 -
      Outer mirror control Outer mirror control ECU Main body ECU Operation of outer mirrors is prohibited U0142
      Active stabilizer control

      • Front active stabilizer control ECU

      • Rear active stabilizer control ECU

      • Steering angle sensor

      • Yaw rate sensor

      • Skid control ECU

      		 Active stabilizer system control is prohibited

      U1108

      U1109

      U0122

      U0126

      U0123

      (Inoperative message is displayed)

      Navigation cooperative operation (Air conditioning)

      (Changes between fresh air mode and recirculation mode automatically based on information from the multi-media module receiver assembly of presence of tunnels)

      		 Multi-media module receiver assembly - - U0073