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CAN COMMUNICATION SYSTEM(for LHD without Central Gateway ECU) FAIL-SAFE CHART

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  1. FAIL-SAFE FUNCTION


    1. When communication fails in any of the CAN bus wires (communication wires), a fail-safe function(s) operates. 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).

      System Function

      1. Control Master

      2. System Related

      3. Control Actuator

      		 Behavior during CAN Failure
      Vehicle Behavior Indicator and Buzzer Diagnostic Trouble Code
      Engine

      Engine System Indicator Display


      • Estimates whether the injectors are clogged and requests that a message be displayed informing the user that the injectors need maintenance.

      • Estimates whether the oil has deteriorated and displays a request to change the oil.

      1. ECM

      2. Combination meter assembly

      3. Combination meter assembly

      		 The meter display cannot be cleared.
      • When there is a transmission stop or when the bus is continuously detected:

      • The system is unable to inform the user that the oil needs to be replaced.

      • The meter display does not clear.


      • When there is a reception stop:

      • The meter display does not clear.

      		 -

      Electrical Load Control

      (Performs idle up according to the electrical load.)

      1. ECM

      2. Air conditioning amplifier assembly, Combination meter assembly

      3. ECM

      		 Idle up according to the electrical load is not performed. The idling speed changes. -

      Air Conditioning-linked Control


      • Performs idle up according to the compressor load. Performs air conditioning cut control.

      • Performs air conditioning cut control.

      1. ECM

      2. Air conditioning amplifier assembly

      3. Air conditioning amplifier assembly

      		 Air conditioning-linked control does not operate (cannot perform idle up). Air conditioning does not operate. -
      Engine

      PTC Heater

      (Performs idle up according to requests from the PTC heater [including coolant heater] or heater system.)

      1. ECM

      2. Air conditioning amplifier assembly

      3. ECM

      		 The PTC heater does not operate (permission is not granted).
      • When there is a transmission stop or when the bus is continuously detected:

      • The PTC heater does not operate.


      • When there is a reception stop:

      • The idling speed changes.

      • Heater performance becomes worse.

      • The PTC heater does not operate.

      		 -

      Charging Control

      (Performs idle up according to charging requests.)

      1. ECM

      2. Air conditioning amplifier assembly, Combination meter assembly

      3. ECM

      • Idle up according to charging requests is not performed.

      • Charging control is not prohibited.

      • Idle up according to charging requests is not performed.

      • The taillights flicker.

      • The blower airflow volume changes.

      		 -

      Spring Vibration Damping Control

      (Improves the behavior of the spring due to outside disturbances using transient driving force control.)

      1. ECM

      2. Brake actuator assembly (skid control ECU)

      3. ECM

      • Spring vibration damping control does not operate.

      • The behavior of the springs due to outside disturbances is not improved using transient driving force control.

      		 Nothing -

      ECT System Indicator

      (Displays shift, switch and mode information to the meter.)

      1. ECM

      2. -

      3. Combination meter assembly

      		 Nothing ECT system indicators do not illuminate. -

      Eco Driving Indicator

      (Displays information to the driver to encourage eco-driving.)

      1. ECM

      2. -

      3. Combination meter assembly

      		 Nothing No information is displayed. -
      Engine

      Integrated Control (VDM)

      (Estimates the driver requested torque based on the accelerator pedal operation and performs torque characteristic control according to driving conditions so that driveability, acceleration performance and acceleration feeling are improved.)

      1. ECM

      2. Brake actuator assembly (skid control ECU), Airbag sensor assembly, Spiral with sensor cable sub-assembly (steering angle sensor)

      3. ECM

      		 Does not estimate the driver requested torque based on the accelerator pedal operation and does not perform torque characteristic control according to driving conditions and as a result, driveability, acceleration performance and acceleration feeling are not improved. Does not estimate the driver requested torque based on the accelerator pedal operation and does not perform torque characteristic control according to driving conditions and as a result, driveability, acceleration performance and acceleration feeling are not improved. -

      Eco Control

      (Performs electronic throttle control according to fuel consumption.)

      1. ECM

      2. Combination meter assembly, Air conditioning amplifier assembly

      3. ECM

      		 Eco mode does not operate. Eco mode does not operate. -

      AI-SHIFT Control

      (Controls the automatic transmission in order to improve engine braking power and acceleration feel.)

      1. ECM

      2. Radio and display receiver assembly

      3. ECM

      		 AI-SHIFT control does not operate. Nothing -

      Coast Downshift/Heater Requested Upshift Delay

      (Changes the coast downshift point based on the air conditioning load. Performs heater requested upshift delay.)

      1. ECM

      2. Air conditioning amplifier assembly

      3. ECM

      		 Coast downshift does not operate. Coast downshift shock becomes stronger. -

      Cruise Control

      (Adjusts engine throttle valve opening amount automatically to maintain vehicle speed)

      1. ECM

      2. Combination meter assembly, Brake actuator assembly (skid control ECU)

      3. ECM

      		 Nothing The cruise control main indicator illuminates. -

      Eco-run Control

      (Performs engine starting and stopping using eco-run control.)

      1. ECM

      2. Engine stop and start ECU

      3. Engine stop and start ECU

      		 Eco-run control is prohibited. Eco-run control is prohibited. U1103
      Air Conditioning

      Air Conditioning Control


      • Adjusts the engine speed by performing idle up, etc.

      • Adjusts the air temperature, airflow mode and airflow volume according to the engine coolant temperature.

      • Adjusts the engine coolant temperature compensation map information and switches the value for determining whether the compressor is locked according to the engine type.

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • While the ignition switch to ON, control is performed with the engine coolant temperature set to the default value of 80°C (176°F).

      • While the ignition switch to ON, control is performed with the default setting for the engine type (the default setting depends on the vehicle type).

      		 Nothing U0100

      Compressor Control

      (Determines whether the compressor is locked according to NE.)

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • When the ignition switch is ON: Control is performed with the default value (0 rpm).

      • When the ignition switch is not ON: Nothing

      		 Nothing U0100

      Panel Dimming Control

      (Outputs dimming information to the LIN panel according to the display dimming information.)

      1. Air conditioning amplifier assembly

      2. Combination meter assembly

      3. -

      		 While the ignition switch to ON, previous values are maintained (during a reset, dimming control is performed). Cannot switch between dimming states. U0155

      Outside Temperature Compensation Control

      (Changes the air conditioning system operation state and adjusts the outside temperature display value according to the vehicle speed.)

      1. Air conditioning amplifier assembly

      2. Combination meter assembly

      3. -

      		 While the ignition switch to ON, control is performed with the default vehicle speed value (0 km/h [0 mph]).

      • The accuracy of the displayed outside temperature becomes less reliable.

      • The proper airflow volume level for the air conditioning system may be incorrect (while the ignition switch to ON).

      		 U0155
      Navigation System

      Eco Navigation Display

      (Displays the average fuel consumption history and a graph indicating the fuel consumption in 1 minute intervals.)

      1. Navigation receiver assembly, Radio and display receiver assembly

      2. ECM, Combination meter assembly, Brake actuator assembly (skid control ECU)

      3. -

      • The fuel consumption per minute display update on the eco navigation screen (fuel consumption per minute screen) stops (the fuel consumption per minute history graph is not cleared).

      • Stops updating the average fuel consumption history on the eco navigation (eco drive screen).

      • If the distance to empty is being displayed on the eco navigation (eco drive screen), the value displayed is cleared due to a distance to empty data communication stop.

      • The 1 minute fuel consumption graph on the eco navigation (eco drive) display is not updated for 1 minute or more.

      • The most recent value for the fuel consumption interval graph on the eco navigation (eco drive) screen is cleared.

      • The numbers of the distance to empty displayed on the fuel consumption screen of the eco navigation (eco drive) display are cleared.

      • U0100

      • U0129

      • U0155
      Navigation System

      Destination Determination

      (Determines the destination of the vehicle and selects the display language, time zone, etc. based on destination symbols, destination package information, etc.)

      1. Navigation receiver assembly, Radio and display receiver assembly

      2. Combination meter assembly

      3. -

      		 Determines the destination according to the last received value and operates accordingly (if there is no last received value, the system operates using the default value). The time zone and language selection screens do not match the destination. U0155

      Rear View Monitor Control

      (Displays the rear view of the vehicle.)

      1. Navigation receiver assembly, Radio and display receiver assembly

      2. ECM

      3. -

      		 Nothing Cannot switch to the camera screen. U0100

      Meter-linked Function

      (Changes display based on customization information set through the meter. Outputs the customization information set in the system.)

      1. Radio and display receiver assembly

      2. Combination meter assembly

      3. -

      		 Maintains the last valid state. Nothing -
      Eco Run

      Stop and Start System

      (Stops the engine when the vehicle is stopped.)

      1. Engine stop and start ECU

      2. ECM, Brake actuator assembly (skid control ECU), Air conditioning amplifier assembly, Airbag sensor assembly, Combination meter assembly, 4 wheel drive control ECU, Spiral with sensor cable sub-assembly (steering angle sensor)

      3. ECM

      • During eco-run: Restarts

      • Not during eco-run: Prohibits eco-run

      		 ECO driving indicator light blinks.

      • U0100

      • U0114

      • U0121

      • U0126

      • U0151

      • U0155

      • U0164
      Steering Angle Sensor

      Steering Sensor

      (Detects steering wheel angle)

      1. Spiral with sensor cable sub-assembly (steering angle sensor)

      2. Brake actuator assembly (skid control ECU)

      3. -

      		 Sends steering sensor data information every 12 seconds. Nothing -
      AFS

      Leveling

      (Adjust the vertical beam axis direction of the headlights according to the pitch angle calculated using the wheel speeds and vehicle height sensor value.)

      1. Headlight leveling ECU assembly

      2. ECM, Brake actuator assembly (skid control ECU), Combination meter assembly

      3. Headlight leveling ECU assembly

      		 Leveling control stops (beam axis position is stopped at position when malfunction was detected). Nothing

      • U0100

      • U0129

      • U0142

      Leveling Indicator


      • Monitors leveling system malfunctions and when a malfunction is detected, sends an indicator illumination request to the meter.

      • Detects LED headlight open circuits and sends an indicator illumination request to the meter.

      1. Headlight leveling ECU assembly

      2. ECM, Brake actuator assembly (skid control ECU), Combination meter assembly

      3. Combination meter assembly

      		 Nothing Nothing

      • U0100

      • U0129

      Headlight Cleaner

      (Performs headlight cleaner control according to the operation status of the low beam headlights and front window washer switch.)

      1. Headlight leveling ECU assembly

      2. Brake actuator assembly (skid control ECU), Combination meter assembly

      3. -

      		 Stops headlight cleaner operation. Nothing U0129
      Meter

      Vehicle Speed Display

      (Displays the vehicle speed on the speedometer according to the vehicle speed signal from the skid control ECU.)

      1. Combination meter assembly

      2. Brake actuator assembly (skid control ECU)

      3. -

      		 Signal is considered to be 0.

      • The speedometer displays 0 km/h (0 mph).

      • The drive monitor stops calculating.

      		 U0129

      Tachometer

      (Displays information on the tachometer.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 Signal is considered to be 0.

      • The tachometer displays 0 rpm.

      • The drive monitor stops calculating.

      		 U0100

      Engine Coolant Temperature Receiver Gauge

      (Controls the engine coolant temperature receiver gauge according to the temperature signals.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 The temperature gauge needle is at the middle of the "C" mark or below. Nothing -

      Airbag

      (Turns the SRS warning light on and off.)

      1. Combination meter assembly

      2. Airbag sensor assembly

      3. -

      		 Signal is considered to be "Active". Signal is considered to be "Active". U0151

      SLIP Warning

      (Turns the SLIP warning light on and off.)

      1. Combination meter assembly

      2. Brake actuator assembly (skid control ECU)

      3. -

      		 Signal is considered to be "Active". The SLIP indicator illuminates. U0129

      ECT/ENG System Display

      (Turns the temperature gauge command high engine coolant temperature warning display on and off.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 The needle of the engine coolant temperature gauge is at the C mark or below. The needle of the engine coolant temperature gauge is at the C mark or below. -
      Brake

      Anti-lock Brake System Control

      (Prevents the wheels from locking during sudden stops.)

      1. Brake actuator assembly (skid control ECU)

      2. Airbag sensor assembly

      3. Brake actuator assembly (skid control ECU)

      • During control: After ending backup control (stabilizing the vehicle), the system changes to normal braking and prohibits control.

      • Not during control: Control cannot start.

      • The ABS indicator illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0124

      Vehicle Stability Control/Traction Control

      (Suppresses vehicle instability, such as drift when cornering and wheel slippage when accelerating. During vehicle dynamics integrated management control, vehicle integrated control which includes electronic steering control is performed.)

      1. Brake actuator assembly (skid control ECU)

      2. ECM, Airbag sensor assembly, Spiral with sensor cable sub-assembly (steering angle sensor)

      3. Brake actuator assembly (skid control ECU)

      • During control: After ending backup control (stabilizing the vehicle), the system changes to normal braking and prohibits control.

      • Not during control: Control cannot start.

      • The ABS indicator illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0124

      • U0126
      Brake

      Hill-start Assist Control 3

      (Maintains the brake oil pressure for 2 seconds when the brake pedal is depressed further.)

      1. Brake actuator assembly (skid control ECU)

      2. ECM, Airbag sensor assembly, Spiral with sensor cable sub-assembly (steering angle sensor)

      3. Brake actuator assembly (skid control ECU)

      • During control: After ending backup control (pressure reduction control), the system changes to normal braking and prohibits control, or control continues, and after normal control finishes, prohibits control.

      • Not during control: Control cannot start.

      • The ABS indicator illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0124

      • U0126

      Eco Run Hold Control

      (Maintains brake fluid pressure while switching from the brake pedal to the accelerator pedal and restarting the engine. The fluid pressure is maintained for a maximum of 2 seconds. Afterwards, it takes 1 second for the pressure to be released.)

      1. Brake actuator assembly (skid control ECU)

      2. ECM, Airbag sensor assembly, Spiral with sensor cable sub-assembly (steering angle sensor), Engine stop and start ECU

      3. Brake actuator assembly (skid control ECU)

      • During control: After ending backup control (which stabilizes the vehicle), the system changes to normal braking and prohibits this control.

      • Not during control: Control cannot begin.

      • The ABS indicator illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0124

      • U0126
      Entry and Start

      Entry and Start Function


      • Entry lock/unlock and entry back door unlatch

      • Entry warning

      • Entry illumination (Dome light illumination, etc.)

      1. Certification ECU (smart key ECU assembly)

      2. Certification ECU (smart key ECU assembly)

      3. Combination meter assembly

      		 Nothing

      • Entry lock/unlock and entry back door unlatch

      • Entry warning does not operate.

      • Entry illumination does not operate.

      • The answer back function continuously operates when an unlock operation is performed.

      		 U0155

      1. Certification ECU (smart key ECU assembly)

      2. Engine stop and start ECU

      3. Combination meter assembly

      		 Nothing Falsely outputs the entry warning. U1103

      1. Certification ECU (smart key ECU assembly)

      2. ECM

      3. Combination meter assembly

      		 The previous value is maintained. Falsely outputs the entry warning. U0100

      Ignition Switch Lettering Illumination Control

      (Operates the ignition switch lettering illumination in conjunction with the dome light illumination, etc.)

      1. Certification ECU (smart key ECU assembly)

      2. Combination meter assembly, Certification ECU (smart key ECU assembly)

      3. Certification ECU (smart key ECU assembly)

      • If the ignition switch letters are illuminated due to the dome light, the illumination turns off.

      • When the DC cut fuse is removed and the ignition switch letters are illuminated due to the panel illumination, the illumination turns off.

      • The previous value is maintained.

      • If the ignition switch letters are not illuminated, they do not illuminate.

      • If the ignition switch letters are illuminated due to the panel illumination, the illumination does not turn off.

      • If the ignition switch letters are illuminated due to the dome light, the illumination turns off.

      • When the DC cut fuse is removed and the ignition switch letters are illuminated due to the panel illumination, the illumination turns off.

      		 -
      Airbag

      TC DTC Output Service

      (While TC = ON is being received from the ECM, a DTC is output in response to the request from the combination meter assembly.)

      1. Combination meter assembly

      2. ECM

      3. Airbag sensor assembly

      		 If the TC signal is lost during TC service (TC = ON), the TC is determined to be OFF and TC service ends. Nothing -

      Collision Detection Signal

      (Notifies the system of a collision in order to perform fuel cut when a vehicle collision occurs.)

      1. ECM

      2. Airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Airbag Warning Light Control

      (Sends airbag warning light illumination information.)

      1. Combination meter assembly

      2. Airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Seat Belt Warning Control

      (Sends information about the passengers in order to turn the seat belt warning on and off.)

      1. Combination meter assembly

      2. Airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Trigger Signal/Autonomous Transmission

      (Outputs the yaw rate sensor signal.)

      1. Airbag sensor assembly

      2. Brake actuator assembly (skid control ECU)

      3. Brake actuator assembly (skid control ECU)

      		 The yaw rate sensor information signal is sent at regular intervals every 0.012 seconds. Nothing -

      Event Data Recorder (EDR)

      (Records conditions, such as the vehicle speed, the amount the accelerator is depressed, and the shift lever position when the event data recorder recording conditions are met.)

      1. Airbag sensor assembly

      2. ECM, Brake actuator assembly (skid control ECU), Spiral with sensor cable sub-assembly (steering angle sensor), Combination meter assembly

      3. -

      • When there is a communication error, a failure notification is received from the other device, or an invalid value is recorded in the EDR when the communication failure occurs.

      • When there is a periodic problem, the previous value is maintained.

      		 Nothing -
      4WD

      Switching between 2WD and 4WD

      (The vehicle speed is judged and switching between H2 and H4 is performed due to a user switching operation.)

      1. 4 wheel drive control ECU

      2. Combination meter assembly, Brake actuator assembly (skid control ECU)

      3. 4 wheel drive control ECU, Combination meter assembly

      		 Switching between H2 and H4 is prohibited.

      When transmission is lost:


      • The 4WD indicator does not turn on when switching from H2 to H4 or when in H4 mode.

      When there is a reception stop:


      • Switching does not operate.

      • The 4WD indicator blinks.

      • The message is displayed on multi-information display.

      		 U0122

      H-L Switching

      (The vehicle speed is judged, etc. and switching between H and L is performed due to a user switching operation.)

      1. 4 wheel drive control ECU

      2. ECM, Combination meter assembly, Brake actuator assembly (skid control ECU)

      3. 4 wheel drive control ECU, Combination meter assembly

      		 Switching between H4 and L4 is prohibited.

      When transmission is lost:


      • The 4LO indicator does not turn on when switching from H4 to L4 or when in L4 mode.

      When there is a reception stop:


      • Switching does not operate.

      • The 4LO indicator blinks.

      • The message is displayed on multi-information display.

      • U0100

      • U0122
      4WD

      Rear Differential Lock Switching

      (The vehicle speed is judged and rear differential lock switching is performed due to a user switching operation.)

      1. 4 wheel drive control ECU

      2. Combination meter assembly, Brake actuator assembly (skid control ECU)

      3. 4 wheel drive control ECU, Combination meter assembly

      		 Switching between rear differential lock and free is prohibited.

      When transmission is lost:


      • The rear differential lock indicator does not turn on when switching from rear differential free to lock or when rear differential is locked.

      When there is a reception stop:


      • Switching does not operate.

      • The rear differential lock indicator blinks.

      		 U0122

      Wheel Speed Fail Characteristics Control

      (Even when there is a wheel speed sensor open circuit, 4WD switching is performed via user operation.)

      1. 4 wheel drive control ECU

      2. ECM, Brake actuator assembly (skid control ECU)

      3. 4 wheel drive control ECU

      • Switching between H2 and H4 is prohibited.

      • Switching between H4 and L4 is prohibited.

      • Switching does not operate.

      • The 4LO indicator blinks.

      • The message is displayed on multi-information display.

      		 U0100

      Vehicle Speed Restriction Function

      (Vehicle speed is restricted when front differential is hot.)

      1. 4 wheel drive control ECU

      2. Brake actuator assembly (skid control ECU)

      3. ECM, Combination meter assembly

      		 The vehicle speed restriction flag and vehicle speed restriction value is set as the fail-safe value.

      • The buzzer sounds and the 4WD indicator blinks during vehicle speed restriction.

      • A message is not displayed on the multi-information display.

      		 -