Toyota Tundra Service Manual: Fail-safe Chart

FAIL-SAFE CHART

1. FAIL-SAFE FUNCTION

(a) When communication fails in any of the main wires (communication lines) due to a short circuit or other causes, the fail-safe function, which is specified for each system, operates to prevent the system from malfunctioning.

(b) The table below shows the effects on each system when communication is impossible. For further details, refer to each system.

Function

Control Master

(Main ECU to determine controls)

System Related

Fail-safe Operation

Driver Detectable

DTC Detection

(ECU that stored DTC)

Electrical Load Control

(Idle up according to the electrical load is performed.)

ECM

  • Air conditioning amplifier assembly
  • Main body ECU (multiplex network body ECU)

Idle up according to the electrical load is not performed.

The idling speed changes.

-

Air Conditioning Coordinated Control

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

ECM

Air conditioning amplifier assembly

Air conditioning-linked control does not operate.

  • Cannot perform idle up
  • Cannot air conditioning cut control.

Air conditioner does not operate.

-

Charging Control

(Performs idle up according to charging requests.)

ECM

  • Air conditioning amplifier assembly
  • Main body ECU (multiplex network body ECU)

Idle up according to charging requests is not performed.

Idle up according to charging requests is not performed.

-

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 drivability, acceleration performance and acceleration feeling are improved.)

ECM

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

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.)

ECM

Main body ECU (multiplex network body ECU)

Power/snow mode driving control cannot be performed.

  • Power/snow mode driving control cannot be performed.
  • Indicator does not turn on.
  • MIL illuminates

-

AI-SHIFT Control

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

ECM

  • Brake actuator assembly (skid control ECU)
  • Radio and display receiver assembly
  • Navigation receiver assembly

AI-SHIFT control does not operate.

AI-SHIFT control does not operate.

-

Coast Downshift

(Changes the coast downshift point based on the air conditioning load.)

ECM

Air conditioning amplifier assembly

Coast downshift does not operate.

Coast downshift shock becomes stronger.

-

Heater Requested Upshift Delay

(Performs heater requested upshift delay.)

Cruise Control

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

ECM

  • Combination meter assembly
  • Brake actuator assembly (skid control ECU)
  • Millimeter wave radar sensor assembly
  • Cruise control does not operate.
  • Cancel the dynamic radar cruise control
  • Indicator does not turn on or off (maintains prevlous value)
  • Cruise control does not operate.
  • Cruise control main indicator light blinks

-

Engine Control

(Performs fuel supply analysis and alcohol concentration learning.)

ECM

Combination meter assembly

Alcohol concentration learning is not performed.

Drivability worsens and the engine may stall due to the delay of alcohol concentration learning.

U0155

(ECM)

Brake system function

  • ETC
  • VSC
  • Dynamic radar cruise control
  • Hill start assist control
  • Pre-collision brake control

Brake actuator assembly (skid control ECU)

  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • Airbag sensor assembly
  • ECM
  • Forward recognition camera

Prohibits control

  • VSC warning light illuminates
  • ABS warning light illuminates
  • U0073
  • U0100
  • U0114
  • U0123
  • U0126

(Brake actuator assembly [skid control ECU])

Automatic Brake

Brake control with bracket relay

  • Brake actuator assembly (skid control ECU)
  • Airbag sensor assembly

Disable Automatic Brake

(Manual Brake is available)

Malfunction notification message is displayed.

  • U0123
  • U0129

(Brake control with bracket relay)

Automatic & Manual Brake

Brake control with bracket relay

Combination meter assembly

Disable TBC Brake

(Including Manual Brake)

Malfunction notification message is displayed.

  • U0073
  • U0155

(Brake control with bracket relay)

2WD-4WD Switching Limitation

(Switching between 2WD and 4WD is prohibited when the vehicle speed is outside the acceptable range.)

4 wheel drive control ECU (4WD control ECU)

Brake actuator assembly (skid control ECU)

Switching between 2WD and 4WD is prohibited.

Indicator light blinks

-

High-Low Switching Limitation

(Prohibits High-Low switching when the vehicle speed or engine speed is outside the acceptable range or the A/T is not in N during the A/T status check.)

4 wheel drive control ECU (4WD control ECU)

  • ECM
  • Brake actuator assembly (skid control ECU)

High-Low switching prohibited.

Indicator light blinks

-

Center Differential Lock Switching Control

(Center differential lock switching is prohibited when there is a vehicle speed violation or large difference in wheel speeds.)

4 wheel drive control ECU (4WD control ECU)

Brake actuator assembly (skid control ECU)

Center differential lock switching is prohibited.

Indicator light blinks

-

L4F Switching Control

(Switching to L4F is prohibited and the operation is performed with L4L when VSC is malfunctioning.)

4 wheel drive control ECU (4WD control ECU)

Brake actuator assembly (skid control ECU)

L4F switching is prohibited

Indicator light blinks

-

Control Performed During Low Temperatures

(Changes the value of the electric current applied to the ACT according to the temperature.)

4 wheel drive control ECU (4WD control ECU)

  • ECM
  • Air conditioning amplifier

Changes to the temperature used for ACT temperature correction control calculations.

-

-

Specialized Control During Wheel Speed Failure

(When there is a wheel speed failure, switching is permitted only when specified conditions are met [the wheel speed malfunction is 1 wheel or more and 3 wheels or less, the brake is applied, the engine speed is low, and all normal wheel speeds are low.])

4 wheel drive control ECU (4WD control ECU)

  • ECM
  • Brake actuator assembly (skid control ECU)

If the wheel speed malfunction is 1 wheel or more and 3 wheels or less, only when the wheel speed failure specified conditions are met, switching is permitted. When 4 wheels are malfunctioning, switching is prohibited (the wheel speed failure specialized control does not operate).

Indicator light blinks.

-

Vehicle Speed Threshold Limitation

(Determines whether the temperature is low or normal and changes the vehicle speed at which shifting from to 2 to 4 is prohibited.)

4 wheel drive control ECU (4WD control ECU)

Air conditioning amplifier

Uses the threshold value for low temperatures.

-

-

Indicator and Buzzer Signal Output

(Outputs a signal indicating the state of the indicators and buzzers, which represent the actuator position and switching status.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

Cruise Control Cancel Signal Output

(Outputs a cruise control cancel signal when center differential switching is not completed even though 5 seconds or more have elapsed from the start of switching.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

L4 State Signal Output

(Outputs a signal when switching to the L4 position is finished.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

4WD State Signal Output

(The ADDSW state is output.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

T/FN State Signal Output

(The NPSW state is output.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

Motor Operation Signal Output

(Outputs the state of the actuator.)

4 wheel drive control ECU (4WD control ECU)

-

The signal cannot be transmitted. Therefore, the signal is not updated.

-

-

Microcomputer Preset Steering

  • Automatically starts the auto-away and auto-return operations for the steering wheel according to a signal that indicates when the key is inserted or removed.
  • Memorizes and recalls the selected driving position according to memory switch operation.
  • Moves the steering wheel to the selected position according to manual switch operation on the steering column cover.

Multiplex tilt and telescopic ECU

  • Combination meter assembly
  • Front power seat switch LH (power seat control ECU)

Nothing

The memory, recall, auto-return and auto-away functions do not operate.

  • U0142
  • U0208
  • B2624

(Multiplex tilt and telescopic ECU)

Tachometer

(The combination meter assembly displays engine speed information via an analog gauge.)

Combination meter assembly

ECM

Tachometer indicates 0 RPM.

-

-

Speedometer

(The combination meter assembly displays vehicle speed information via an analog gauge. The combination meter assembly transmits vehicle speed to other modules.)

Combination meter assembly

Brake actuator assembly (skid control ECU)

Speedometer indicates 0 km/h (0 mph).

-

-

Temperature Gauge

(The combination meter assembly displays engine coolant temperature via an analog gauge.)

Combination meter assembly

ECM

Temperature gauge indicates "C".

-

-

ODO Meter

(The combination meter assembly displays the distance traveled via an LCD display. The combination meter assembly integrates the value it receives, and stores this value in NVM. This value is also used to control the maintenance required indicator.)

Combination meter assembly

Brake actuator assembly (skid control ECU)

Meter will stop odometer accumulation, and the maintenance required indicator will not illuminate.

-

-

A/T Shift Position

(The combination meter assembly displays A/T shift position information via indicators and sequential shift information via an LCD display.)

Combination meter assembly

ECM

Meter will not display A/T shift position or sequential shift gear.

-

-

Brake indicator

(The combination meter assembly will illuminate the brake indicator.)

Combination meter assembly

  • Main body ECU (multiplex network body ECU)
  • Brake actuator assembly (skid control ECU)

Meter will illuminate the brake indicator.

Meter will illuminate the brake indicator.

-

Airbag indicator

(The combination meter assembly controls the airbag indicator.)

Combination meter assembly

Airbag sensor assembly

Meter will illuminate the airbag indicator.

Meter will illuminate the airbag indicator.

-

Driver Seat Belt indicator

(The combination meter assembly controls the driver seat belt indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

will illuminate the driver's seat belt indicator.

will illuminate the driver's seat belt indicator.

-

Door Ajar indicator

(The combination meter assembly controls the door ajar indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will retain the current state of the door ajar indicator.

-

-

High Beam indicator

(The combination meter assembly controls the high beam indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will retain the current state of the high beam indicator

-

-

Taillight indicator

(The combination meter assembly controls the taillight indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will retain the current state of the tail indicator.

-

-

Headlight indicator

(The combination meter assembly controls the headlight indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will retain the current state of the head indicator.

-

-

Front Fog indicator

(The combination meter assembly controls the front fog indicator.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will retain the current state of the front fog indicator.

-

-

Cruise indicator

(The combination meter assembly controls the cruise indicator.)

Combination meter assembly

ECM

Combination meter assembly will retain the current state of the cruise indicator.

-

-

ABS indicator

(The combination meter assembly controls the ABS indicator.)

Combination meter assembly

Brake actuator assembly (skid control ECU)

Combination meter assembly will illuminate the ABS indicator.

Combination meter assembly will illuminate the ABS indicator.

-

VSC OFF indicator

(The combination meter assembly controls the VSC OFF indicator.)

Combination meter assembly

Brake actuator assembly (skid control ECU)

Combination meter assembly will retain the current state of the VSC OFF indicator.

-

-

Slip indicator

(The combination meter assembly controls the slip indicator.)

Combination meter assembly

Brake actuator assembly (skid control ECU)

Combination meter assembly will retain the current state of the slip indicator.

-

-

4WD indicator

(The combination meter assembly controls the 4WD indicator.)

Combination meter assembly

4 wheel drive control ECU (4WD control ECU)

Combination meter assembly will retain the current state of the 4WD indicator.

-

-

Seat Belt (P) indicator

(The combination meter assembly controls the passenger seat belt indicator.)

Combination meter assembly

Airbag sensor assembly

Combination meter assembly will retain the current state of the passenger seat belt indicator.

-

-

Seat Belt Buzzer

(The combination meter assembly controls the seat belt buzzer.)

Combination meter assembly

  • Main body ECU (multiplex network body ECU)
  • Airbag sensor assembly
  • Brake actuator assembly (skid control ECU)
  • ECM

Combination meter assembly will retain the current state of the seat belt buzzer.

-

-

Key In Ignition Reminder Buzzer

(The combination meter assembly controls the key in ignition reminder buzzer.)

Combination meter assembly

Main body ECU (multiplex network body ECU)

Combination meter assembly will not sound the key in ignition reminder buzzer.

-

-

Park Brake Set Buzzer

(The combination meter assembly controls the park brake set buzzer.)

Combination meter assembly

  • Main body ECU (multiplex network body ECU)
  • Brake actuator assembly (skid control ECU)

Combination meter assembly will not sound the park brake set buzzer.

-

-

Door Ajar Buzzer

(The combination meter assembly controls the door ajar buzzer.)

Combination meter assembly

  • Main body ECU (multiplex network body ECU)
  • Brake actuator assembly (skid control ECU)

Combination meter assembly will not sound the door ajar buzzer.

-

-

Shift Reject Buzzer

(The combination meter assembly controls the shift reject buzzer.)

Combination meter assembly

ECM

Combination meter assembly will retain the current state of the shift reject buzzer.

-

-

Outside Temperature Display

(The combination meter assembly controls the display of outside temperature in the accessory meter.)

Combination meter assembly

Air conditioning amplifier assembly

Combination meter assembly will not display outside temperature.

-

-

Alarm Control

Main body ECU (multiplex network body ECU)

ECM

  • Alarm control does not operate by back door wireless lock enabling signal
  • Shift to disarming by engine RPM data does not operate

-

U0100

(Main body ECU [multiplex network body ECU])

Door Lock Control

(Lock/unlock control [Key linked operation, Key lock-in prevention, Auto lock])

Main body ECU (multiplex network body ECU)

  • Airbag sensor assembly
  • Combination meter assembly
  • ECM
  • Key linked lock/unlock control operates
  • Speed-linked auto lock control does not operate
  • Shift-linked auto lock control operate
  • Shift-linked auto unlock control does not operate
  • Auto lock/unlock change control does not operates

-

  • U0100
  • U0101
  • U0151
  • U0155

(Main body ECU [multiplex network body ECU])

Daytime Running Light Control

Main body ECU (multiplex network body ECU)

ECM

Daytime running light control does not operate.

-

U0100

(Main body ECU [multiplex network body ECU])

LED Headlight Alarm

Main body ECU (multiplex network body ECU)

ECM

LED headlight alarm does not operate.

-

U0100

(Main body ECU [multiplex network body ECU])

Wireless

(Wireless control)

Main body ECU (multiplex network body ECU)

Airbag sensor assembly

  • It is no problem, because KLEG status is kept at communication failure.
  • Wireless door lock/unlock does not operate by the back door wireless lock enabling signal

-

-

Diagnostic/C-BEST

(Diagnostic phase 4 communication)

Main body ECU (multiplex network body ECU)

-

-

-

-

Display Auto Dimmer

(Display auto dimmer control)

Main body ECU (multiplex network body ECU)

Combination meter assembly

  • Operate display auto dimmer without tail cancel
  • When the light sensor illumination level is lower than the display dimming level, the display/indicator dims

-

U0155

(Main body ECU [multiplex network body ECU])

Tire Pressure Monitoring System

(Gateway control [CAN and BERKES])

Tire pressure warning ECU and receiver

Combination meter assembly

Transmit initial communication value to BERKES side.

After the TPMS indicator blinks for 1 minute, it illuminates.

U0155

(Main body ECU [multiplex network body ECU])

Automatic High Beam System

Main body ECU (multiplex network body ECU)

Forward recognition camera

Auto high light control does not operate (combination meter indicator blinks).

AHB indicator blinks.

U023A

(Main body ECU [multiplex network body ECU])

Seat and Mirror

(Memory Control [Adjustment of the seat and tilt and telescopic steering and mirror, reverse-linked outer mirror])

Main body ECU (multiplex network body ECU)

  • Outer mirror control ECU assembly RH
  • Outer mirror control ECU assembly LH
  • Combination meter assembly
  • ECM

Stops the operation of the seat, tilt and telescopic steering wheel, etc.

-

  • U0155
  • U0199
  • U0200
  • U0208
  • U1115

(Main body ECU [multiplex network body ECU])

Compressor Control/Lock Judgement

(Controls air conditioning compressor lock condition.)

Air conditioning amplifier assembly

ECM

  • Engine RPM data: "0"
  • Lock judgement: "disable"
  • Several periods inside processing is late

-

B1499

(Air conditioning amplifier assembly)

Air Inlet Control/Forced Inside Air Control

(Forces recirculation mode at high water temperatures.)

Air conditioning amplifier assembly

ECM

  • Internal air circulation at high water temperature: "disable"
  • Several periods inside processing is late

-

-

Air Level Control/Warm-Up Control

(Controls blower based on water temperature.)

Air conditioning amplifier assembly

ECM

  • Engine water temperature: "80 °C (176 °F)"
  • Air level control warm-up control: "disable"
  • Several periods inside processing is late

-

-

Air Outlet Control/Automatic FOOT/DEF Control

(Controls air outlet for automatic FOOT/DEF mode.)

Air conditioning amplifier assembly

ECM

  • Engine water temperature: "80 °C (176 °F)"
  • Air outlet control automatic FOOT/DEF control: "disable"
  • Several periods inside processing is late

-

-

Shift Up Delay Control/Heater Performance

(Heater performance request to transmission system.)

Air conditioning amplifier assembly

ECM

  • Engine water temperature: "80 °C (176 °F)"
  • Heater performance assistance request signal to transmission system: "disable"
  • Several periods inside processing is late

-

-

Engine Model Judgement

(Engine model information used for air conditioning configuration purposes.)

Air conditioning amplifier assembly

ECM

  • Engine model information: control with default value.
  • Several periods inside processing is late

-

-

Outside Temperature Display Output

(This system reads the outside air temperature sensor and filters/calculates the value to be used for air conditioning control and outside temperature display.)

Air conditioning amplifier assembly

Combination meter assembly

  • Vehicle speed: "0"
  • Outside temperature indication is not displayed right
  • Several periods inside processing is late

-

-

Air Outlet Control/Automatic FOOT/DEF Control

(Controls air outlet for automatic FOOT/DEF mode.)

Air conditioning amplifier assembly

Combination meter assembly

  • Vehicle speed: "0"
  • Air outlet control automatic FOOT/DEF control: "disable"
  • Several periods inside processing is late

-

-

Rear Defogger Drive Control

(Controls the rear defogger.)

Air conditioning amplifier assembly

Combination meter assembly

  • Vehicle speed: "0"
  • Rear defogger drive extension control: "disable"
  • Several periods inside processing is late

-

-

Air Level Control/Vehicle Speed Compensation

(Controls the blower level based on vehicle speed.)

Air conditioning amplifier assembly

Combination meter assembly

  • Vehicle speed: "0"
  • Air level control/vehicle speed compensation: "disable"
  • Several periods inside processing is late

-

-

Set Temperature Units

(Configures the units of set temperature.)

Air conditioning amplifier assembly

Combination meter assembly

  • Setting temperature indication unit (Centigrade/Fahrenheit): "Only Fahrenheit"
  • Several periods inside processing is late

-

-

Electric Load Restriction Control

(Controls the limiting of electric loads of the air conditioning amplifier assembly.)

Air conditioning amplifier assembly

ECM

  • Electric load restrictions control: "disable"
  • When the LCLVL (CAN signal from ECM): Other than "0"
  • Mirror heater, rear defogger and wiper deicer output cannot stop
  • Several periods inside processing is late

-

-

Blind Spot Monitor

(Warns the driver when the system detects a vehicle in the blind spots of the outer mirrors.)

Blind spot monitor sensor RH

  • Brake actuator assembly (skid control ECU)
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • Main body ECU (multiplex network body ECU)
  • ECM
  • Airbag sensor assembly

Nothing (the previous values are maintained).

  • BSM indicator illuminates (amber)
  • Malfunctions are notified on the multi-information display in the combination meter.
  • U0100
  • U0125
  • U0126
  • U0129
  • U0142

(Blind spot monitor sensor RH)

Light Control

(Light lighting control on the basis of lamp lighting request from the main body ECU [multiplex network body ECU].)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

Mirror under foot illumination does not operate.

Mirror under foot illumination does not operate.

-

Mirror Drive Control

(Drive control of the outer mirror on the basis of mirror switch information and so on from the main body ECU [multiplex network body ECU].)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

Mirror manual operation does not operate.

Mirror manual operation does not operate.

U0142

(Outer mirror control ECU assembly LH/Outer mirror control ECU assembly RH)

Mirror Heater Control

(Drive control of the outer mirror heater on the basis of defogger switch information from the main body ECU [multiplex network body ECU].)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

Mirror heater does not operate.

Mirror heater does not operate.

U0142

(Outer mirror control ECU assembly LH/Outer mirror control ECU assembly RH)

Power Retract Mirror Control

(Power retract mirror drive control of the outer mirror on the basis of mirror switch information and so on from the main body ECU [multiplex network body ECU].)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

Power retract mirror control does not operate.

Power retract mirror control does not operate.

-

Mirror Reverse Control

(Reverse drive control of the outer mirror on the basis of reverse request from the main body ECU [multiplex network body ECU].)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

Reverse mirror shift-linked function does not operate.

Reverse mirror shift-linked function does not operate.

-

Memory Mirror memorization and regeneration control

(Memorization mirror plane position of the outer mirror on the basis of memory request from the main body ECU [multiplex network body ECU] and regeneration drive control to the memorized position.)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Main body ECU (multiplex network body ECU)

  • Mirror regeneration does not operate
  • Mirror memory does not operate
  • Mirror regeneration does not operate
  • Mirror memory does not operate

-

Memory Switch Signal Representation Transmission

(Transmit memory switch signal to CAN)

Main body ECU (multiplex network body ECU)

  • Outer mirror control ECU assembly LH
  • Outer mirror control ECU assembly RH

Nothing

Memory sheet, mirror memory and regeneration does not operate.

-

Tire Pressure Monitoring System

(Monitors tire pressure and warns the driver of low pressure.)

Tire pressure warning ECU and receiver

-

Nothing

-

U0129

(Tire pressure warning ECU and receiver)

Wireless Door Lock

(Locks/unlocks the side door or back door.)

Tire pressure warning ECU and receiver

-

Nothing

-

-

Pre-collision System

(Detects obstacles in front and performs brake assist and brake control in order to lessen damage and avoid collisions.)

Millimeter wave radar sensor assembly

  • Brake actuator assembly (skid control ECU)
  • Airbag sensor assembly
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • ECM
  • Forward recognition camera
  • Brake control with bracket relay

Pre-collision system is stopped.

  • Malfunctions are notified on the multi-information display in the combination meter
  • The buzzer sounds.
  • The PCS warning light blinks.
  • U0100
  • U0125
  • U0126
  • U0129
  • U0137
  • U023A
  • U0235
  • U1002

(Millimeter wave radar sensor assembly)

Dynamic Radar Cruise Control System

(Uses the millimeter wave radar, yaw rate sensor, spiral with sensor cable sub-assembly (steering angle sensor), etc., to recognize and judge the existence of a preceding vehicle, track it, and ensure an appropriate vehicle-to-vehicle distance while driving and stopping. When there are no preceding vehicles, this system allows for constant-speed driving at the set speed.)

Millimeter wave radar sensor assembly

  • Brake actuator assembly (skid control ECU)
  • Airbag sensor assembly
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • ECM

Cruise control system is stopped.

Malfunctions are notified on the multi-information display in the combination meter.

  • U0100
  • U0125
  • U0126
  • U0129

(Millimeter wave radar sensor assembly)

Automatic High Beam System

(Controls the high beams.)

Forward recognition camera

  • Main body ECU (multiplex network body ECU)
  • ECM
  • Brake actuator assembly (skid control ECU)
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • Airbag sensor assembly
  • Keep last value
  • Camera control continues normally. However, AHB signals cannot be sent to the Main body ECU (multiplex network body ECU). As a result, the Main body ECU (multiplex network body ECU) performs malfunction judgment and maintains the condition.
  • Normal control is continued.

AHB indicator illuminates (umber).

U023A

(Main body ECU [multiplex network body ECU])

Lane Departure Alert System

(Warns the driver when the vehicle deviates from its lane.)

Forward recognition camera

  • Brake actuator assembly (skid control ECU)
  • Main body ECU (multiplex network body ECU)
  • Combination meter assembly
  • Airbag sensor assembly
  • Millimeter wave radar sensor assembly
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • The warning is stopped.
  • White line recognition is stopped.
  • Displays messages on the multi-information display.
  • Buzzer
  • U0123
  • U0126
  • U0129
  • U0142
  • U0155
  • U0235

(Forward recognition camera)

Air Conditioning Control

(Performs preset temperature adjustment, vent selection, etc., according to operation of the touch panel switches and integration panel switches on the multi-media screen.)

  • Navigation receiver assembly
  • Radio and display receiver assembly

Air conditioning amplifier assembly

  • 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

(Navigation receiver assembly/Radio and display receiver assembly)

Eco Navigation Display

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

  • Navigation receiver assembly
  • Radio and display receiver assembly
  • ECM
  • Combination meter assembly
  • Brake actuator assembly (skid control ECU)
  • 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 receiver assembly/Radio and display receiver assembly)

Destination Determination

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

  • Navigation receiver assembly
  • Radio and display receiver assembly

Main body ECU (multiplex network body ECU)

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

(Navigation receiver assembly/Radio and display receiver assembly)

Vehicle Customize Function

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

  • Navigation receiver assembly
  • Radio and display receiver assembly
  • Air conditioning amplifier assembly
  • Main body ECU (multiplex network body ECU)
  • Front power seat switch LH (power seat control ECU)
  • Multiplex tilt and telescopic ECU

3 retries are performed (including the first time).

The customize options for items related to the main body ECU (multiplex network body ECU), multiplex tilt and telescopic ECU and front power seat switch LH (power seat control ECU) are not displayed or the settings cannot be saved.

U0073

(Navigation receiver assembly/Radio and display receiver assembly)

Combination Meter Cooperation function

(Synchronizes multi-media module and combination meter settings (language, unit, accent color). The multi-media module sends navigation system turn-by-turn, audio and telephone data.)

  • Navigation receiver assembly
  • Radio and display receiver assembly

Combination meter assembly

Maintains last value.

-

-

Timestamp

(Stores the timestamp information received from the CGW together with the DTC.)

Airbag sensor assembly

Central gateway ECU (network gateway ECU)

When a fail value is received or a communication stop occurs, a separate count is changed to inside the ECU and separate count recognition information is set.

-

-

Collision Detection Signal

(Reports a collision in order to perform a fuel cut, trigger the EDR, perform MCB control or detect millimeter wave radar axis misalignment, etc., during a collision.)

  • ECM
  • Brake actuator assembly (skid control ECU)
  • Millimeter wave radar sensor assembly

Airbag sensor assembly

Nothing

-

-

Airbag Warning Light Control

(Sends airbag warning light illumination information.)

Combination meter assembly

Airbag sensor assembly

Nothing

-

-

Seat Belt Warning Control

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

  • Main body ECU (multiplex network body ECU)
  • Combination meter assembly

Airbag sensor assembly

Nothing

-

-

Trigger Signal/Self Transmission

(Outputs the yaw rate and acceleration sensor signal.)

Airbag sensor assembly

Brake actuator assembly (skid control ECU)

Sends yaw rate sensor information every 0.012 seconds

-

-

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.)

Airbag sensor assembly

  • Millimeter wave radar sensor assembly
  • ECM
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • Brake actuator assembly (skid control ECU)
  • Airbag sensor assembly
  • An invalid value is recorded in the EDR.
  • The previous values are maintained.

-

-

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.)

Airbag sensor assembly

  • Brake actuator assembly (skid control ECU)
  • Blind spot monitor sensor RH
  • Central gateway ECU (network gateway ECU)
  • Millimeter wave radar sensor assembly
  • Forward recognition camera
  • Combination meter assembly
  • Spiral with sensor cable sub-assembly (steering angle sensor)
  • Airbag sensor assembly
  • ECM
  • An invalid value is recorded in the DDR.
  • The previous values are maintained.

-

-

Memory Seat

  • Memorize the position of the seat.
  • Memory recall of the seat position.

Front power seat switch LH (power seat control ECU)

  • ECM
  • Main body ECU (multiplex network body ECU)
  • Multiplex tilt and telescopic ECU
  • Reproduction cancellation in the ignition switch ON
  • Memorize the position and memory recall operation cancellation
  • The tilt and telescopic steering system is not operating.

-

-

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

(Detects the steering wheel angle.)

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

Brake actuator assembly (skid control ECU)

Sends spiral with sensor cable sub-assembly data signal every 0.012 seconds.

VSC OFF indicator light illuminates.

-

Lost Communication Detection

(Monitors the NS and NM frames of the ECU connected to the global bus to detect for ECU communication failures.)

Central gateway ECU (network gateway ECU)

ECUs connected to the global bus

Stores the communication failure time.

-

-

    ECM Communication Stop Mode

    Front Camera Module Communication Stop Mode

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