CAN COMMUNICATION SYSTEM(for LHD without Central Gateway ECU) 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) 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).

      Function

      1. Control Master

      2. System Related

      3. Control Actuator

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

      Electrical Load Control

      (Performs idle up according to the electrical load.)

      1. ECM

      2. Main body ECU (multiplex network body ECU), Air conditioning amplifier assembly, Power steering ECU 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.)

      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. -

      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.

      		 -

      Eco-drive Indicator

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

      1. ECM

      2. -

      3. Combination meter assembly

      		 Nothing No information is displayed. -

      Integrated Control

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

      1. ECM

      2. Brake actuator assembly (skid control ECU), Power steering ECU 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, drivability, 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, drivability, acceleration performance and acceleration feeling are not improved. -

      ECT System Indicator

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

      1. ECM

      2. Main body ECU (multiplex network body ECU)

      3. Combination meter assembly

      		 Nothing ECT system indicators do not illuminate. -

      Cruise Control

      (Adjusts the engine throttle valve opening amount automatically to control the vehicle.)

      1. ECM

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

      3. ECM

      		 Cruise control does not operate.

        w/ Multi-information Display

      • Displays messages on the multi-information display.

      • The cruise indicator do not illuminate.


        w/o Multi-information Display

      • The cruise indicator illuminate.

      		 U0122

      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 Conditioner


      • The idle up engine speed, etc. is calibrated.

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

      • Engine coolant temperature map calibration and compressor judgment value switching based on engine type.

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • When there is a communication stop from the first time the ignition switch is turned to ON: Control is performed with the coolant temperature data set at the default value (80°C [176°F]).

      • When there is a communication stop while the ignition switch is ON: Maintains previous values.

      • When the ignition switch is not ON: Nothing

      		 If a communication stop occurs while the engine coolant temperature is rising, the airflow amount does not rise due to warm up control. -

      • When there is a communication stop from the first time +B is On and there is no DTF data: Control is performed with the engine type set at the default value.

      • When there is a communication stop in a situation other than described above: Maintains previous values.

      • When the ignition switch is not ON: Nothing

      		 When the AUTO SW is depressed, the compressor does not turn ON, or the compressor turns ON when it should not. 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

      		 The number of lines that turn ON by the PTC relay does not increase. -

      Simple Load Control

      (Limits simple electrical load control according to the load control level.)

      1. Air conditioning amplifier assembly

      2. Power steering ECU assembly

      3. -

      • When the ignition switch is ON: Maintains previous values (there is no load control during a reset).

      • When the ignition switch is not ON: Nothing

      		 The DEF relay and PTC relay do not turn ON. U0131

      Destination Determination Control

      (Switches air conditioning control pattern according to destination information.)

      1. Air conditioning amplifier assembly

      2. Main body ECU (multiplex network body ECU)

      3. -

      • When the ignition switch is ON: Maintains previous values.

      • When the ignition switch is not ON: Nothing

      		 The set temperature, unit, and central value on the panel cannot be changed. U0142

      Outside Temperature Compensation Control

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

      1. Air conditioning amplifier assembly

      2. Combination meter assembly

      3. -

      • When the ignition switch is ON: Control is performed with the vehicle speed set at the default value (0 km/h [0 mph]).

      • When the ignition switch is not ON: Nothing

      • When the ignition switch is ON:


        • The reliability of the outside temperature value shown decreases.

        • The system is not able to adjust the air conditioning airflow volume correctly.

      • When the ignition switch is not ON: Nothing

      		 U0155

      Door Lock

      (Operates the lock and unlock [the key-linked function, key lock-in prevention function, etc.].)

      1. Main body ECU (multiplex network body ECU)

      2. ECM, Combination meter assembly Airbag sensor assembly

      3. Main body ECU (multiplex network body ECU)

      • When the ignition switch is ON: Maintains previous values.

      • When the ignition switch is off: The key-linked operation is permitted.

      		 Nothing U0155

      Automatic Dimming of Display

      (Controls the display dimming.)

      1. Main body ECU (multiplex network body ECU)

      2. Combination meter assembly

      3. Main body ECU (multiplex network body ECU)

      		 Automatically performs display dimming control when tail mode is not canceled (when the light sensor illuminance signal value is less than the display dimming value, the interior displays and indicators are dimmed). Nothing U0155

      Illumination

      (Performs illumination control.)

      1. Main body ECU (multiplex network body ECU)

      2. -

      3. Main body ECU (multiplex network body ECU)

      		 The dome light is turned off. The dome light does not turn off immediately after exiting the vehicle. U0327

      Equipment Related

      (Controls gateway between the BERKES equipment and CAN.)

      1. Main body ECU (multiplex network body ECU)

      2. Combination meter assembly, ECM, Air conditioning amplifier assembly

      3. Air conditioning amplifier assembly

      		 Sends an initial communication value to the BERKES. The remote engine start does not operate.

      • U0100

      • U0101

      • U0155

      • U0164

      Diagnostic/C-BEST

      (Diagnostic phase 4 communication.)

      1. -

      2. All ECUs connected to CAN

      3. Main body ECU (multiplex network body ECU)

      		 Exits diagnostic mode. Nothing -

      Lighting Control

      (Performs DRL control)

      1. Main body ECU (multiplex network body ECU)

      2. ECM

      3. Main body ECU (multiplex network body ECU)

      		 Daytime running light control is not performed. Nothing U0100

      Pre-air Conditioner

      (System which lowers the cabin temperature when the air conditioning is operated before entering the vehicle.)

      1. Main body ECU (multiplex network body ECU)

      2. Air conditioning amplifier assembly

      3. Air conditioning amplifier assembly

      		 Pre-air Conditioner operation is prohibited. Nothing U0164

      Tire Pressure Monitor Sensor

      (Monitors the tire pressure and meter speed, etc. and operates the meter indicators and multi-information display [gateway between BERKES and CAN].)

      1. Main body ECU (multiplex network body ECU)

      2. Combination meter assembly

      3. Combination meter assembly

      		 Sends an initial communication value to the BERKES. The tire pressure monitor sensor indicator in the combination meter assembly blinks for 1 minute and then stays illuminated. U0155

      Air Conditioning Control

      (Controls the selecting of the registers, temperature adjustment, etc. according to remote touch operation.)

      1. Radio and display receiver assembly

      2. Air conditioning amplifier assembly

      3. -

      • The air conditioning related indicators are turned off.

      • If the set air temperature is displayed on an external display device, the system clears the set air temperature display.

      • Disables the functions used to operate the air conditioning system.

      		 Displays messages on the multi-information display.

      • U0073

      • U0164

      Eco Navigation Display

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

      1. 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

      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. Radio and display receiver assembly

      2. Main body ECU (multiplex network body ECU)

      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. U0140

      Vehicle Customize Function

      (Changes the behavior and control parameters of various functions (illumination lighting time, etc.) according to the user operation via the screen.)

      1. Radio and display receiver assembly

      2. Air conditioning amplifier assembly, Main body ECU (multiplex network body ECU)

      3. -

      • When a remote communication usage application is performed (customize or remote diagnosis), the information is processed regardless of whether the main body ECU (multiplex network body ECU) has permitted or prohibited remote communication.

      • 3 retries are performed (including the first time).

      		 The customize options for items related to the ACN and BDB ECU are not displayed or the settings cannot be saved.

      • U0073

      • B15F5

      • B15F6

      • B15F7

      • B15F8

      HUD Display Function

      (Displays the navigation intersection guide information on the meter or HUD device.)

      1. Combination meter assembly

      2. Radio and display receiver assembly

      3. -

      		 Nothing Nothing U0073

      Time Stamp Function

      (Matches the relative time from the main body ECU with the absolute time acquired from the GPS.)

      1. Main body ECU (multiplex network body ECU)

      2. Main body ECU (multiplex network body ECU)

      3. -

      		 Nothing Nothing

      • U0073

      • U0140

      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 -

      Timestamp

      (Stores the time when a DTC is stored for confirmation.)

      1. Power steering ECU assembly

      2. Main body ECU (multiplex network body ECU)

      3. Power steering ECU assembly

      		 Nothing Nothing -

      Assist Map Selection

      (Selects the assist map according to the destination information, drivetrain [2WD or 4WD], engine type, etc.)

      1. Power steering ECU assembly

      2. ECM

      3. -

      		 Nothing Nothing -

      DTC Output

      (When the TC signal is on, DTC information is sent according to the polling from meter ECU.)

      1. Power steering ECU assembly, Combination meter assembly

      2. Power steering ECU assembly, Combination meter assembly

      3. Power steering ECU assembly, Combination meter assembly

      		 Nothing Nothing -

      Steering Assist Calculation

      (Changes the assist force according to the vehicle speed.)

      1. Power steering ECU assembly

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

      3. Power steering ECU assembly

      • Even if the engine starts, steering assist does not start (steering assist starts when the vehicle speed is input).

      • As the vehicle speed cannot be determined, control continues with the vehicle speed set at 140 km/h (87 mph).

      		 The EPS warning light illuminates.

      • U0100

      • U0129

      αB Control

      (Performs assist to prevent sliding sideways.)

      1. Power steering ECU assembly

      2. Brake actuator assembly (skid control ECU)

      3. Power steering ECU assembly

      		 α-B control processing is stopped. Nothing -

      Simple Load Control

      (Determines the current power supply and load status, and sends commands to limit control.)

      1. Air conditioning amplifier assembly

      2. Power steering ECU assembly

      3. Air conditioning amplifier assembly

      		 Nothing Nothing -

      Steering Assist Calculation

      (Estimates the steering angle neutral point from the vehicle speed and resolver signal to determine the absolute steering angle.)

      1. Power steering ECU assembly

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

      3. Power steering ECU assembly

      		 Functions that use the estimated steering angle are turned off (after estimation completes due to driving in a straight line, related functions are turned on). Nothing -

      Enter Test Mode

      (Receives the test mode signal and enters test mode.)

      1. Power steering ECU assembly

      2. ECM

      3. Power steering ECU assembly

      		 Nothing Nothing -

      Idle Up

      (When a large assist current is created, a request to perform idle up is sent to the ECM in order to prevent the battery voltage from dropping.)

      1. ECM

      2. Power steering ECU assembly

      3. ECM

      		 Nothing Nothing -

      Warning Light Illumination

      (When the fail-safe function operates, a request to turn on the electronic power steering light is sent to the combination meter.)

      1. Combination meter assembly

      2. Power steering ECU assembly

      3. Combination meter assembly

      		 Nothing Nothing -

      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 0.012 seconds. Nothing -

      ATC-4WD System

      (Controls the driving force distribution between the front and rear wheels according to driving conditions.)

      1. 4WD ECU assembly

      2. ECM, Brake actuator assembly (skid control ECU), Main body ECU (multiplex network body ECU), Spiral with sensor cable sub-assembly (steering angle sensor), Air conditioning amplifier assembly

      3. 4WD ECU assembly

        When transmission is lost:

      • 4WD control is prohibited (the vehicle behaves the same as a 2WD vehicle).


        When there is a reception stop:

      • When the ECM or steering angle sensor is malfunctioning: Control continues using default values.

      • When the skid control ECU is malfunctioning:


        • Control is prohibited (the vehicle behaves the same as a 2WD vehicle).

        • Yaw rate feedback control is prohibited (conventional control continues).

        When there is a transmission stop or when the bus is continuously detected:

      • 4WD indicator light blinks.


        When there is a reception stop or a cyclic malfunction:

      • 4WD indicator light illuminates.

      • U0073

      • U0100

      • U0126

      • U0129

      ATC-4WD System

      (Controls the driving force distribution between the front and rear wheels according to driving conditions.)

      1. 4WD ECU assembly

      2. ECM, Brake actuator assembly (skid control ECU), Main body ECU (multiplex network body ECU), Spiral with sensor cable sub-assembly (steering angle sensor), Air conditioning amplifier assembly

      3. 4WD ECU assembly

        During a cyclic malfunction:

      • During a steering angle sensor malfunction:


        • Control continues by maintaining previous values.

        • Control continues using default values.

      • During an ECM malfunction: Control continues using default values.

      • When the skid control ECU is malfunctioning:


        • Control continues using the default values (yaw rate feedback control).

        • Control continues, but the feedback of the speed difference between the front and rear wheels is prohibited.

      • When the air conditioning amplifier assembly or main body ECU is malfunctioning: Control continues using default values.

        When there is a transmission stop or when the bus is continuously detected:

      • 4WD indicator light blinks.


        When there is a reception stop or a cyclic malfunction:

      • 4WD indicator light illuminates.

      • U0073

      • U0100

      • U0126

      • U0129

      ATC-4WD System

      (Controls the driving force distribution between the front and rear wheels according to driving conditions.)

      1. 4WD ECU assembly

      2. ECM, Brake actuator assembly (skid control ECU), Main body ECU (multiplex network body ECU), Spiral with sensor cable sub-assembly (steering angle sensor), Air conditioning amplifier assembly

      3. 4WD ECU assembly

        When a continuous bus is detected:

      • Control is prohibited (the vehicle behaves the same as a 2WD vehicle).

        When there is a transmission stop or when the bus is continuously detected:

      • 4WD indicator light blinks.

      • U0073

      • U0100

      • U0126

      • U0129

      Vehicle Speed Display

      (Operates the speedometer according to the vehicle speed signals from the skid control ECU.)

      1. Combination meter assembly

      2. Brake actuator assembly (skid control ECU)

      3. -

      		 Signal is considered to be "0".

      • Displays 0 km/h (0 mph) in the speedometer.

      • The drive monitor stops calculating.

      		 U0129

      Tachometer

      (Displays the tachometer.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 Signal is considered to be "0".

      • Displays 0 rpm in the tachometer.

      • The drive monitor stops calculating.

      		 U0100

      Airbag

      (Turns the airbag warning light on and off.)

      1. Combination meter assembly

      2. Airbag sensor assembly

      3. -

      		 Signal is considered to be "Active". The airbag warning light illuminates. U0151

      EPS Warning Light

      (Turns the EPS warning light on and off.)

      1. Combination meter assembly

      2. Power steering ECU assembly

      3. -

      		 Signal is considered to be "Active". The EPS warning light illuminates. U0131

      SLIP Indicator Light

      (Turns the SLIP indicator 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. -

      ECT/ENG System Display

      (Displays the coolant temperature.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 Signal is considered to be "0". The needle of the engine coolant temperature gauge is at the C mark or below. -

      Anti-lock Brake System Control

      (Prevents the wheels from locking when suddenly stopping.)

      1. Brake actuator assembly (skid control ECU)

      2. Airbag sensor assembly

      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 warning light illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0124

      Vehicle Stability Control/Traction Control/Vehicle Dynamics Integrated Management 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 (which stabilizes the vehicle), the system changes to normal braking and prohibits this control.

      • Not during control: Control cannot begin.

      • The ABS warning light illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0124

      • U0126

      Hill-start Assist Control 3

      (Maintains the brake fluid 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 (which stabilizes the vehicle), the system changes to normal braking and prohibits this control.

      • Not during control: Control cannot begin.

      • The ABS warning light 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 warning light illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0126

      TC DTC Output Service

      (While TC = ON is being received from the engine, 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 -

      Timestamp

      (Records DTCs and timestamps received from the main body ECU.)

      1. Airbag sensor assembly

      2. Main body ECU (multiplex network body ECU)

      3. -

      		 Changes to a separate count inside the ECU and sets separate count recognition information when it receives a fail value or communication stops. 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. Main body ECU (multiplex network body ECU), Combination meter assembly

      2. Airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Trigger Signal/Autonomous Transmission

      (Outputs the yaw rate and acceleration sensor signal.)

      1. Airbag sensor assembly

      2. Brake actuator assembly (skid control ECU)

      3. Brake actuator assembly (skid control ECU)

      		 Sends yaw rate sensor data information. 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)

      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 -

      Drive Data Recorder (DDR)

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

      1. Airbag sensor assembly

      2. ECM, Brake actuator assembly (skid control ECU), Main body ECU (multiplex network body ECU), Combination meter assembly, Power steering ECU assembly, Spiral with sensor cable sub-assembly (steering angle sensor), Airbag sensor 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 DDR when the communication failure occurs.

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

      		 Nothing -

      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), Main body ECU (multiplex network body ECU), Power steering ECU assembly, Air conditioning amplifier assembly, Airbag sensor assembly, Combination meter assembly

      3. ECM

      • During eco-run: Restarts

      • Not during eco-run: Prohibits eco-run

      		 ECO driving indicator light blinks.

      • U0100

      • U0121

      • U0131

      • U0140

      • U0151

      • U0155

      • U0164