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) 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

      		 Vehicle Behavior User Notification Diagnostic Trouble Code

      Air Conditioning

      (Performs compressor solenoid drive control according to the air conditioning cut signal.)

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • When there is a transmission stop: No behavior change.

      • When there is a reception stop: Operation is prohibited.

      • When there is a periodic malfunction: Previous values maintained.

      		 Nothing -

      Air Conditioning

      (Performs PTC drive control according to the PTC heater drive prohibition signal.)

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • When there is a transmission stop: No behavior change.

      • When there is a reception stop: Operation is prohibited.

      • When there is a periodic malfunction: Previous values maintained.

      		 Nothing -

      Air Conditioning

      (Performs magnetic clutch drive control according to the air conditioning cut signal.)

      1. Air conditioning amplifier assembly

      2. ECM

      3. -

      • When there is a transmission stop: No behavior change.

      • When there is a reception stop: Operation is prohibited.

      • When there is a periodic malfunction: Previous values maintained.

      		 Nothing -

      Air Conditioning

      (Performs ambient temperature correction control according to the ambient temperature signal.)

      1. Air conditioning amplifier assembly

      2. Combination meter assembly

      3. -

      • When there is a transmission stop: No behavior change.

      • When there is a reception stop: When the ignition switch is turned from off to ON and there is no backup, control is performed at a temperature of 15°C [59°F]. (Previous values are maintained for all other cases.)

      • When there is a periodic malfunction: Previous values maintained.

      		 Nothing -

      Tachometer

      (Displays the tachometer.)

      1. Combination meter assembly

      2. ECM

      3. -

      		 The tachometer displays 0 rpm.

      • The tachometer displays 0 rpm.

      • The drive monitor stops calculating.

      		 U0100

      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, Combination meter assembly

      3. -

      		 Previous values are maintained during signal interruption and leveling control continues. Nothing

      • U0100

      • U0155

      Auto Leveling Indicator Light

      (Monitors leveling system malfunctions and when a malfunction is detected, illuminates/blinks the indicator in the meter.)

      1. Headlight leveling ECU assembly

      2. Headlight leveling ECU assembly

      3. Combination meter assembly

      		 Maintains the auto leveling indicator light state.

      • When there is a transmission stop:


        • Valve checks when the ignition switch is turned to ON are not performed.

        • Indicator light does not blink when initialization is incomplete and vehicle specifications have not been written.

      • When there is a periodic malfunction: The blinking cycle when the indicator light blinks (when initialization is incomplete and vehicle specifications have not been written) is irregular.

      		 -

      LED Open Circuit Detection

      (When there is an LED malfunction, illuminates the LED headlight warning light according to the malfunction signal from the headlight leveling ECU assembly.)

      1. Headlight leveling ECU assembly

      2. Headlight leveling ECU assembly

      3. Combination meter assembly

      		 Maintains the LED headlight warning light state.

      • Valve checks when the ignition switch is turned to ON are not performed.

      • If communication is lost when there is an LED malfunction, the LED headlight warning light does not illuminate.

      		 -

      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. 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.

      • The PTC heater does not operate.

      • The idling speed changes.

      • Heater performance becomes worse.

      		 -

      Charging Control

      (Performs idle up according to charging requests.)

      1. Certification ECU (smart key ECU assembly)

      2. Air conditioning amplifier 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 tail lights flicker and the blower airflow volume changes.

      		 -

      Eco-drive Indicator

      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 (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), Spiral with sensor cable sub-assembly (steering angle sensor), Center airbag sensor assembly

      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

      (Indicates the shift position, states of switches, system modes, etc.)

      1. ECM

      2. -

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

      3. ECM

      		 The cruise control does not operate. The cruise indicator blinks. -

      Smart Entry and Start Function

      (Smart entry and start warnings)

      1. Certification ECU (smart key ECU assembly)

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

      3. Combination meter assembly

      		 Maintains previous values.

      • When there is a transmission stop or a continuous bus off condition is detected: The smart entry and start warnings (key lock-in prevention warning, passenger has brought key out of vehicle warning, key reminder warning, etc.) do not operate.

      • When there is a reception stop with the meter ECU or a periodic malfunction: The smart entry and start warnings (key lock-in prevention warning, passenger has brought key out of vehicle warning, key reminder warning, etc.) operate incorrectly.

      • When there is a reception stop with the ECM: Incorrect smart entry and start warnings are output.

      • U0100

      • U0155

      Push Start (Power Supply Switching)

      (Using the push start switch signal as a trigger, sends a starter drive request when the power supply automatically switches and conditions are met.)

      1. Certification ECU (smart key ECU assembly)

      2. ECM, Combination meter assembly

      3. -

      		 Nothing When the engine is turned off, the smart key indicator light blinks red according to a "vehicle information malfunction" judgment.

      • U0100

      • U0155

      Start Control

      (Starts the engine when the push start switch is pushed once.)

      1. Certification ECU (smart key ECU assembly)

      2. ECM

      3. -

      		 When there is a CAN communication malfunction, the direct line determines that starter turnoff has occurred and cranking is stopped. Nothing U0100

      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. Center 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. Center airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Airbag Warning Light Control

      (Sends airbag warning light illumination information.)

      1. Combination meter assembly

      2. Center airbag sensor assembly

      3. -

      		 Nothing Nothing -

      Trigger Signal/ Autonomous Transmission

      (Outputs the yaw rate and acceleration sensor signal.)

      1. Center 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. Center 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 -

      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 0.12 seconds. Nothing -

      Anti-lock Brake System Control

      (Prevents the wheels from locking when suddenly stopping.)

      1. Brake actuator assembly (skid control ECU)

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

      • U0100

      • U0124

      • U0126

      Hill-start Assist Control 2

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

      1. Brake actuator assembly (skid control ECU)

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

      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 warning light illuminates.

      • The SLIP indicator illuminates.

      • U0073

      • U0100

      • U0124

      • U0126