CAN COMMUNICATION SYSTEM FAIL-SAFE CHART


  1. FAIL-SAFE FUNCTION


    1. When communication fails in any of the CAN bus lines (communication lines), 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 Control Master System Related Fail-safe Operation Driver Detectable

      DTC Detection

      (ECU that stored DTC)

      Air Conditioning Control


      • Corrects engine speed, such as for idle up.

      • Controls outlet air temperature, outlet mode change and airflow volume based on engine coolant temperature signal.

      • Corrects engine coolant temperature map and changes compressor lock judgment value.

      Air conditioning amplifier assembly ECM Control is performed based on default coolant temperature of 80°C (176°F). -

      U0100

      (Air conditioning amplifier assembly)

      Compressor Control


      • Judges compressor lock according to engine speed.

      Air conditioning amplifier assembly ECM Control is performed based on default engine speed of 0 rpm. -

      U0100

      (Air conditioning amplifier assembly)

      Simple Load Control


      • Performs electric load control according to load control level signal.

      Air conditioning amplifier assembly Power steering ECU with motor assembly Load control is not performed. -

      U0131

      (Air conditioning amplifier assembly)

      Panel Dimming Control


      • Outputs dimmer signal to LIN connected panels according to display dimmer signal.

      Air conditioning amplifier assembly Main body ECU (Multiplex network body ECU) Dimming mode and non-dimming mode cannot be switched. -

      U0142

      (Air conditioning amplifier assembly)

      Destination Identification Control


      • Changes air conditioning control pattern according to destination.

      Air conditioning amplifier assembly Main body ECU (Multiplex network body ECU) Maintains the latest state. -

      U0142

      (Air conditioning amplifier assembly)

      Ambient Temperature Correction Control


      • Switches air conditioning system operation condition and corrects value of displayed ambient temperature according to vehicle speed signal.

      Air conditioning amplifier assembly Combination meter assembly Control is performed based on default vehicle speed of 0 km/h (0 mph).
      • Correction level for displayed ambient temperature declines.

      • Correction level for outlet airflow declines.

      U0155

      (Air conditioning amplifier assembly)

      Fuel Consumption Display


      • Displays graph of fuel consumption per minute and history of total fuel consumption.


      • Navigation receiver assembly

      • Radio and display receiver assembly


      • ECM

      • Brake actuator assembly

      • Combination meter assembly

      When communication with ECM or skid control ECU is interrupted:


      • Display is not updated.

      When communication with combination meter is interrupted:


      • Display is not updated.

      • Numeric part of driveable mileage is cleared.

      -

      U0100

      U0129

      U0155

      (Navigation receiver assembly)

      (Radio and display receiver assembly)

      Destination Identification


      • Identifies destination based on destination and destination package information, and selects the time zone and language used for the display.


      • Navigation receiver assembly

      • Radio and display receiver assembly

      Main body ECU (Multiplex network body ECU) Destination is identified based on information received before communication is interrupted. Time zone and language selection screen are different from actual destination.

      U0140

      (Navigation receiver assembly)

      (Radio and display receiver assembly)

      Vehicle Customization Function


      • Allows changing of operation and control conditions for vehicle functions via multi-display operation.


      • Navigation receiver assembly

      • Radio and display receiver assembly


      • Smart key ECU assembly (Certification ECU)

      • Main body ECU (Multiplex network body ECU)

      • Position control ECU and switch assembly (for Driver side)

      • Multiplex tilt and telescopic ECU


      • Customization via multi-display is not possible, but customization via main body ECU is possible.

      • When an application that uses remote communication is activated (customization/remote diagnosis), the process will be performed regardless of main body ECU remote communication permit/prohibit state.

      Customizable items are not displayed.

      U0073

      (Navigation receiver assembly)

      Door Lock


      • Controls key linked and automatic door lock/unlock function, key confinement prevention function, etc.

      Main body ECU (Multiplex network body ECU)
      • ECM

      • Combination meter assembly


      • Speed sensitive automatic lock control does not occur.

      • Shift linked automatic lock control does not occur.

      • Shift linked automatic unlock control does not occur.

      • Automatic lock/unlock cannot be changed.

      -

      U0100

      U0155

      (Main body ECU (Multiplex network body ECU))

      Display Automatic Dimming


      • Display dimming control.

      Main body ECU (Multiplex network body ECU) Combination meter assembly Automatic dimming control for displays does not operate when taillights are turned on. -

      U0155

      (Main body ECU (Multiplex network body ECU))

      Illumination Control Main body ECU (Multiplex network body ECU)
      • ECM

      • Smart key ECU assembly (Certification ECU)


      • Interior lights turn off.

      • Inside handle light turn off.

      When communication with smart key ECU is interrupted:


      • Interior lights do not turn off right after getting out of the vehicle.

      U0100

      U0327

      (Main body ECU (Multiplex network body ECU))

      Entry Function/Wireless Control Main body ECU (Multiplex network body ECU) Smart key ECU assembly (Certification ECU) Entry lock/unlock control is not possible. -

      U0327

      (Main body ECU (Multiplex network body ECU))

      Seat and Mirror Control Main body ECU (Multiplex network body ECU)
      • Position control ECU and switch assembly (for Driver side)

      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      • Multiplex tilt and telescopic ECU

      • Smart key ECU assembly (Certification ECU)

      • Combination meter assembly


      • Memory function does not operate.

      • Mirrors cannot be adjusted.

      -

      U0199

      U0200

      U0208

      U0155

      U0327

      U1115

      (Main body ECU (Multiplex network body ECU))

      Parking Assist System Control


      • Judges shift lever position.

      • Judges vehicle speed.

      Clearance warning ECU Assembly
      • ECM

      • TCM

      • Combination meter assembly

      • Main body ECU (Multiplex network body ECU)

      Obstacle detection is stopped. -

      When communication with ECM or TCM is interrupted:


      • U0101

        (Clearance warning ECU Assembly)

      When communication with Main body ECU (Multiplex network body ECU) is interrupted:


      • U0142 (Clearance warning ECU Assembly)

      When communication with combination meter is interrupted:


      • U0155

        (Clearance warning ECU Assembly)

      Electric Load Control


      • Performs idle up according to electric loads.

      ECM
      • Power steering ECU with motor assembly

      • Main body ECU (Multiplex network body ECU)

      • Air conditioning amplifier assembly

      Idle up according to electric loads is not performed. - -

      Air Conditioning Cooperative Operation


      • Performs idle up according to compressor load.

      • Performs air conditioning cut control.

      ECM Air conditioning amplifier assembly

      Air conditioning system does not use cooperative controls.

      (Idle up is not performed.)

      Air conditioning system does not operate. -

      Charge Control


      • Performs idle up according to charging request.

      Smart key ECU assembly (Certification ECU)
      • Main body ECU (Multiplex network body ECU)

      • Air conditioning amplifier assembly

      Idle up according to charging request is not performed. Taillights flicker and blower airflow changes. -

      Eco Control


      • Adjusts throttle response in consideration of actual fuel economy.

      ECM
      • Main body ECU (Multiplex network body ECU)

      • Air conditioning amplifier assembly

      Eco mode does not operate. - -

      Coast Downshift Timing Change According to Air Conditioning Load


      • Delays upshifts according to warm-up request.


      • ECM

      • ECT

      Air conditioning amplifier assembly Coast downshift does not occur. Coast downshift shock reduction performance deteriorates. -

      Power Steering Control


      • Calculates assist current according to torque sensor value and vehicle speed and drives motor.

      Power steering ECU with motor assembly
      • ECM

      • Brake actuator assembly

      • Steering sensor

      When communication with ECM is interrupted:


      • Power steering assist not provided.

      When communication with skid control ECU is interrupted:


      • Control continues based on a default speed of 100 km/h (62 mph) because vehicle speed is indeterminable.

        (Steering wheel feels heavy when the vehicle speed is below 100 km/h (62 mph) and feels light at speeds above 100 km/h (62 mph).)

      EPS warning light illuminates.

      U0100

      U0129

      (Power steering ECU with motor assembly)

      Steering Assist Calculation


      • Changes assist force based on vehicle speed.

      Power steering ECU with motor assembly Brake actuator assembly

      Control continues based on a default speed of 100 km/h (62 mph) because vehicle speed is indeterminable.

      (Steering wheel feels heavy when the vehicle speed is below 100 km/h (62 mph) and feels light at speeds above 100 km/h (62 mph).)

      EPS warning light illuminates.

      U0129

      (Power steering ECU with motor assembly)

      Steering/Steering Angle Sensor Initialization and Zero Point Learning Power steering ECU with motor assembly Brake actuator assembly Steering initialization and zero point learning are not performed. EPS warning light illuminates.

      U0129

      (Power steering ECU with motor assembly)

      Assist Map Selection


      • Selects proper assist map according to destination, engine type, etc.

      Power steering ECU with motor assembly
      • ECM

      • Brake actuator assembly

      Default map is used to assist because proper assist map cannot be selected.

      (Steering feel may be different.)

      EPS warning light illuminates.

      U0100

      U0129

      (Power steering ECU with motor assembly)

      Entry Function


      • Entry lock/unlock, entry luggage compartment open.

      • Warning.

      • Performs entry illumination

        (Interior illumination etc).


      • Main body ECU (Multiplex network body ECU)

      • Smart key ECU assembly (Certification ECU)


      • Main body ECU (Multiplex network body ECU)

      • Combination meter assembly

      Entry unlock is performed again.
      • Entry lock/unlock or entry luggage compartment open does not operate.

      • Warning functions (Key confinement, Key not in vehicle, Key reminder etc.) do not operate, Key confinement prevention control does not operate.

      • Entry illumination does not operate.

      U0142

      U0155

      (Smart key ECU assembly (Certification ECU))

      Wireless Function


      • Locks and unlocks doors, etc. via remote operation.

      Main body ECU (Multiplex network body ECU) Smart key ECU assembly (Certification ECU) Wireless lock, unlock and luggage compartment opener do not operate. - -

      Engine Switch Backlighting Control


      • Turns on/off engine switch illumination linked with interior lights etc.

      Smart key ECU assembly (Certification ECU) Main body ECU (Multiplex network body ECU) Engine switch backlighting does not illuminate according to interior lights operation. -

      U0142

      (Smart key ECU assembly (Certification ECU))

      Meter Display


      • Displays vehicle condition and controls indicator lights.

      Combination meter assembly
      • ECM

      • Brake actuator assembly

      • Airbag sensor assembly

      • Power steering ECU with motor assembly

      • Main body ECU (Multiplex network body ECU)

      Lights do not illuminate or lights always illuminate. Lights do not illuminate properly or do not illuminate at all.

      U0100

      U0129

      U0131

      U0142

      U0151

      (Combination meter assembly)

      Vehicle Speed Display Combination meter assembly Brake actuator assembly Vehicle speed display remains at 0 km/h (0 mph). -

      U0129

      (Combination meter assembly)

      Tachometer


      • Displays engine speed.

      Combination meter assembly ECM The needle points at 0 rpm. -

      U0100

      (Combination meter assembly)

      Coolant Temperature Display Combination meter assembly ECM Display is turned off. - -

      Engine Start/Stop Switch

      (Power Source Mode Change)


      • Using start/stop switch signal as trigger, changes power source mode automatically and requests starter operation when conditions are met.

      Smart key ECU assembly (Certification ECU) ECM - -

      U0100

      (Smart key ECU assembly (Certification ECU))

      ABS/TRC/VSC Control Brake actuator assembly
      • ECM

      • Steering sensor

      • Airbag sensor assembly

      Control stops. Warning lights and indicators illuminate.

      U0073

      U0100

      U0123

      U0126

      (Brake actuator assembly)

      Power Tilt and Power Telescopic Steering Column Control


      • Starts steering wheel auto return or auto away based on a key removal or insertion signal or equivalent.

      Multiplex tilt and telescopic ECU Main body ECU (Multiplex network body ECU) - Auto return/away control does not operate.

      U0142

      (Multiplex tilt and telescopic ECU))

      Lighting System


      • Adjusts headlights vertical aiming according to wheel speed and vehicle pitch angle determined using vehicle height sensor.

      • Swings headlights left or right according to wheel speed and turn radius determined using steering angle.

      AFS ECU
      • ECM

      • TCM

      • Brake actuator assembly

      • Steering sensor

      • Main body ECU (Multiplex network body ECU)

      Control stops. AFS indicator blinks.

      U0100

      U0101

      U0126

      U0129

      U0142

      (AFS ECU)

      Parking Assist Monitor


      • Monitors the shift position signal, steering angle signal and vehicle speed, and displays the predicted path guide lines on the screen based on the steering angle when reversing.

      Rear television camera assembly
      • ECM

      • Steering sensor

      • Brake actuator assembly

      • Main body ECU (Multiplex network body ECU)

      • Clearance warning ECU assembly

      • Radio and display receiver assembly (for Radio and Display Type (w/ Parking Assist Monitor System without Parallel Parking Assist Function))

      • Power steering ECU with motor assembly

      Parking assist monitor function is prohibited.
      • Predicted path guide lines are not displayed.

      • All guide lines and the clearance sonar icon are not displayed.

      U0100

      U0126

      U0129

      U0131

      U0140

      U0163

      U1110

      (Rear television camera assembly)

      Seat Position Memory System


      • Controls the seat position based on operation conditions.

      Position control ECU and switch assembly (for Driver side)
      • Main body ECU (Multiplex network body ECU)

      • ECM

      • Combination meter assembly

      • Smart key ECU assembly (Certification ECU)

      • Multiplex tilt and telescopic ECU

      Controls the seat position based on operation conditions. - -
      Mirror Surface Adjustment
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      Main body ECU (Multiplex network body ECU) Mirror surface position cannot be memorized or recalled. -

      U0142

      (Outer mirror control ECU assembly)

      Mirror Heaters
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)


      • Air conditioning amplifier assembly

      • Main body ECU (Multiplex network body ECU)

      Mirror heaters do not operate. -

      U0142

      (Outer mirror control ECU assembly)

      Mirror Retract/Return Operation
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      Main body ECU (Multiplex network body ECU) Mirrors cannot be retracted or returned. - -
      Reverse-shift Linked Door Mirror Operation
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      Main body ECU (Multiplex network body ECU) Reverse-shift linked door mirror operation is prohibited. - -
      Mirror Surface Position Memory and Recall
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      Main body ECU (Multiplex network body ECU) Mirror surface position cannot be memorized or recalled. - -

      Seat Memory Switch Signal Forwarding


      • Transmits memory switch signal via the CAN bus.

      Main body ECU (Multiplex network body ECU)
      • Outer mirror control ECU assembly (for Driver side)

      • Outer mirror control ECU assembly (for Front passenger side)

      Seat position memory settings cannot be memorized or recalled. - -

      Blind Spot Monitor Control


      • Detects vehicle in blind spot of adjacent lane and informs driver.

      Blind spot monitor sensor RH
      • ECM

      • Steering sensor

      • Brake actuator assembly

      • Main body ECU (Multiplex network body ECU)

      Blind spot monitor control is prohibited. Displays messages on the multi-information display.

      U0100

      U0126

      U0129

      U0142

      U0232

      (Blind spot monitor sensor RH)