CAN COMMUNICATION SYSTEM FAIL-SAFE CHART


  1. FAIL-SAFE FUNCTION


    1. When communication fails in any of the CAN bus lines (communication lines), a fail-safe function(s) will operate. The fail-safe function that is specified for each system operates to prevent those systems from malfunctioning.

    2. The following table shows the effects on each system when communication is impossible. (For further details, see the pages for each system.)

      Function Control Master System Related Fail-safe Operation Driver Detectable

      DTC Detection

      (ECU that stored DTC)

      Air Conditioning Control


      • Corrects engine speed, such as for idle up.

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

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

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

      U0100

      (Air conditioning amplifier assembly)

      Compressor Control


      • Judges compressor lock according to engine speed.

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

      U0100

      (Air conditioning amplifier assembly)

      Simple Load Control


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

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

      U0131

      (Air conditioning amplifier assembly)

      Panel Dimming Control


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

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

      U0142

      (Air conditioning amplifier assembly)

      Destination Identification Control


      • Changes air conditioning control pattern according to destination.

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

      U0142

      (Air conditioning amplifier assembly)

      Insolation Correction Control


      • Corrects air conditioning system control operation according to value of solar sensor.

      		 Air conditioning amplifier assembly Main body ECU (multiplex network body ECU) While the engine switch on (IG), previous values are maintained. -

      U0142

      (Air conditioning amplifier assembly)

      Ambient Temperature Correction Control


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

      		 Air conditioning amplifier assembly Combination meter assembly Control is performed based on default vehicle speed of 0 km/h (0 mph).

      • Correction level for displayed ambient temperature declines.

      • Correction level for outlet airflow declines.

      U0155

      (Air conditioning amplifier assembly)

      Air Conditioning Eco Mode Control


      • Limits air conditioning system control.

      		 Air conditioning amplifier assembly ECM Maintains the latest state (Maintained in normal condition after reset). -

      U0100

      (Air conditioning amplifier assembly)

      Door Lock


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

      		 Main body ECU (multiplex network body ECU)

      • ECM

      • Combination meter assembly

      • Airbag sensor assembly

      • Speed sensitive automatic lock control does not occur.

      • Shift linked automatic lock control does not occur.

      • Automatic lock/unlock cannot be changed.

      		 -

      U0100

      U0101

      U0151

      U0155

      (Main body ECU (multiplex network body ECU))

      Display Automatic Dimming


      • Display dimming control.

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

      U0155

      (Main body ECU (multiplex network body ECU))

      Back Door Opener


      • Performs back door opener control and power back door one motion open control.

      		 Main body ECU (multiplex network body ECU)

      • Multiplex network door ECU

      • Combination meter assembly

      • Back door opener control is prohibited.

      • The back door operation start answer back (hazard warning light/buzzer) does not operate.

      • The one motion power back door does not operate.

      		 -

      U0155

      U0230

      (Main body ECU (multiplex network body ECU))
      Illumination Control Main body ECU (multiplex network body ECU)

      • ECM

      • Certification ECU (smart key ECU assembly)

      • Engine stop and start ECU

      • The interior lights remain off when the electrical key transmitter sub-assembly is close to any of the doors.

      • The interior lights remain on without being dimmed when the shift lever is moved from P to any position other than P.

      • The interior lights remain on when the engine has been started.

      • The interior lights turn off.

      		 -

      U0101

      U0327

      (Main body ECU (multiplex network body ECU))

      Seat and Mirror Control


      • Controls the memory function (the seat and mirror position adjustments).

      		 Main body ECU (multiplex network body ECU)

      • Position control ECU and switch assembly RH (for RHD)

      • Position control ECU and switch assembly LH (for LHD)

      • Multiplex tilt and telescopic ECU

      • Outer mirror control ECU assembly (for driver side)

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

      • Combination meter assembly

      • Certification ECU (smart key ECU assembly)

      • Memory function does not operate.

      • When recording the memory call, the operation stops due to a time out when waiting for the verification results.

      		 -

      U0155

      U0199

      U0200

      U0208

      U0327

      U1115

      (Main body ECU (multiplex network body ECU))

      Smart Beam


      • Controls the high beam automatically when the forward recognition camera detects a preceding vehicle or an oncoming vehicle.

      		 Main body ECU (multiplex network body ECU)

      • Forward recognition camera

      • Headlight ECU sub-assembly LH

      		 Smart beam system does not operate. Displays messages on the multi-information display.

      U0182

      U023A

      (Main body ECU (multiplex network body ECU))

      Engine System Indicator Display


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

      • Estimates whether oil has deteriorated and requests that a message be displayed informing user that oil needs to be replaced.

      		 ECM Combination meter assembly

      • System is unable to inform user that oil needs to be replaced or injectors need maintenance.

      • Combination meter display cannot be cleared.

      		 - -

      Electric Load Control


      • Performs idle up according to electric load.

      		 ECM

      • Air conditioning amplifier assembly

      • Power steering ECU assembly

      • Main body ECU (multiplex network body ECU)

      		 Idle up according to electric load is not performed. Not possible. (Idle speed changes.) -

      Air Conditioning Cooperative Operation


      • Performs idle up according to compressor load.

      • Performs air conditioning cut control.

      		 ECM Air conditioning amplifier assembly Air conditioning system does not use cooperative controls. (Idle up is not performed.) Air conditioning system does not operate. -

      PTC Heater


      • Performs idle up when there is a heat demand signal that requires operation of the PTC heater.

      		 ECM Air conditioning amplifier assembly PTC heater does not operate.

      • Engine idle speed changes.

      • Heating performance deteriorates.

      		 -

      Charge Control


      • Performs idle up according to charging request.

      		 ECM

      • Air conditioning amplifier assembly

      • Main body ECU (multiplex network body ECU)

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

      Eco Control


      • Adjusts throttle response in consideration of actual fuel economy.

      		 ECM Air conditioning amplifier assembly Eco mode does not operate. - -

      ECT System Indicator Display


      • Meter display (Displays shift position, states of switches, system modes, etc.)

      		 ECM Combination meter assembly Indicator light does not illuminate. - -

      Coast Downshift Timing Change According to Air Conditioning Load


      • Delays upshifts according to warm-up request.

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

      Cruise Control


      • Controls vehicle speed by adjusting throttle valve angle automatically.

      		 ECM

      • Skid control ECU (brake actuator assembly)

      • Combination meter assembly

      		 Cruise control does not operate. Displays messages on the multi-information display.

      U012287

      (ECM)

      Stop and Start Control


      • Starts and stops the engine using the stop and start control.

      		 ECM Engine stop and start ECU Stop and start control does not operate. -

      U110387

      (ECM)

      Stop and Start System


      • Stops the engine when the vehicle is stationary.

      		 Engine stop and start ECU

      • Air conditioning amplifier assembly

      • Skid control ECU (brake actuator assembly)

      • ECM

      • Power steering ECU assembly

      • Steering sensor

      • Main body ECU (multiplex network body ECU)

      • Airbag sensor assembly

      • Absorber control ECU

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • When driving in eco drive mode, the engine starts.

      • When not driving in eco drive mode, eco drive cannot be performed.

      		 Stop and start cancel indicator light blinks.

      U0100

      U0121

      U0123

      U0126

      U0131

      U0140

      U0151

      U0164

      (Engine stop and start ECU)

      Power Steering Control


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

      		 Power steering ECU assembly

      • ECM

      • Skid control ECU (brake actuator assembly)

      • Airbag sensor assembly

      • Steering sensor

      		 Assist force restricted. -

      U0100

      U0129

      (Power steering ECU assembly)

      VDIMα System


      • Calculates current to be used for steering assist according to commanded value from VSC, and then operates motor.

      • Skid control ECU (brake actuator assembly)

      • Power steering ECU assembly

      		 Skid control ECU (brake actuator assembly) VDIMα control is stopped. - -

      LKA System


      • Calculates current to be used for steering assist according to commanded values from VSC, and then operates motor.

      • Power steering ECU assembly

      • Driving support ECU assembly

      • Skid control ECU (brake actuator assembly)

      • Steering sensor

      • Forward recognition camera

      		 LKA control is stopped. -

      U0129

      (Power steering ECU assembly)

      Stop and Start Control


      • Continues power steering assist while the engine is stopped by the stop and start system.

      		 Power steering ECU assembly Engine stop and start ECU Stop and Start control is stopped. - -

      Entry Function


      • Entry lock/unlock and back door unlatch

      • Warning

      • Performs entry illumination (Interior illumination, etc.).

      • Main body ECU (multiplex network body ECU)

      • Certification ECU (smart key ECU assembly)

      • Main body ECU (multiplex network body ECU)

      • Combination meter assembly

      • ECM

      • Engine stop and start ECU

      		 Entry unlock is performed again.

      • Entry lock/unlock or back door unlatch does not operate.

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

      • Entry illumination does not operate.

      U0100

      U0142

      U0155

      U1103

      (Certification ECU (smart key ECU assembly))
      Entry Function/Wireless Control Main body ECU (multiplex network body ECU)

      • Main body ECU (multiplex network body ECU)

      • Certification ECU (smart key ECU assembly)

      		 Entry lock/unlock control is not possible. -

      U0142

      (Certification ECU (smart key ECU assembly))

      Engine Switch Backlighting Control


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

      		 Certification ECU (smart key ECU assembly)

      • Main body ECU (multiplex network body ECU)

      • Combination meter assembly

      		 Engine switch backlighting does not illuminate according to interior lights operation. -

      U0142

      (Certification ECU (smart key ECU assembly))

      Security Indicator Display Function


      • Displays immobiliser and security status.

      		 Certification ECU (smart key ECU assembly) Main body ECU (multiplex network body ECU) Security indicator cannot display security status correctly (security indicator blinks or illuminates when in armed state or alarm sounding state). -

      U0142

      (Certification ECU (smart key ECU assembly))
      Vehicle Speed Display Combination meter assembly Skid control ECU (brake actuator assembly) Speedometer is controlled based on a default vehicle speed of 0 km/h (0 mph).

      • ABS warning light illuminates.

      • Slip indicator light illuminates.

      • Brake warning light illuminates.

      U0129

      (Combination meter assembly)
      Tachometer Display Combination meter assembly ECM Needle of tachometer remains at 0 rpm. MIL illuminates.

      U0100

      (Combination meter assembly)

      Meter Display


      • Displays vehicle condition and controls indicator lights.

      		 Combination meter assembly

      • Power steering ECU assembly

      • Airbag sensor assembly

      • Driving support ECU assembly

      • Headlight ECU sub-assembly LH

      • Tire pressure warning ECU and receiver

      • Air conditioning amplifier assembly

      • ECM

      		 Lights do not illuminate or lights remain illuminated. Abnormal light operation

      U0131

      U0151

      U0182

      U1104

      (Combination meter assembly)
      ABS control Skid control ECU (brake actuator assembly)

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      When control is being performed:


      • When back-up control (vehicle behavior stabilization) is complete, braking returns to normal and further control is prohibited.

      When control is not being performed:


      • Control will not be started.

      • Brake warning light illuminates.

      • ABS warning light illuminates.

      • Brake hold operated indicator light blinks.

      U0073

      U0124

      (Skid control ECU (brake actuator assembly))
      VSC/TRC/VDIM control Skid control ECU (brake actuator assembly)

      • ECM

      • Steering sensor

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      When control is being performed:


      • When back-up control (vehicle behavior stabilization) is complete, braking returns to normal and further control is prohibited.

      When control is not being performed:


      • Control will not be started.

      • ABS warning light illuminates.

      • SLIP indicator illuminates.

      • Brake hold operated indicator light blinks.

      U0073

      U0100

      U0124

      U0126

      (Skid control ECU (brake actuator assembly))

      Hill-start Assist Control


      • Maintains the brake hydraulic pressure to the 4 wheels for 2 seconds with the brake pedal released when starting off on an uphill.

      		 Skid control ECU (brake actuator assembly)

      • ECM

      • Steering sensor

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      		 Control cannot be performed.

      • ABS warning light illuminates.

      • SLIP indicator illuminates.

      • Brake hold operated indicator light blinks.

      U0073

      U0100

      U0124

      U0126

      (Skid control ECU (brake actuator assembly))

      Brake Hold Control


      • Maintains the brake oil pressure when the vehicle is stopped.

      		 Skid control ECU (brake actuator assembly)

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • ECM

      When control is being performed:


      • When back-up control (vehicle behavior stabilization) is complete, braking returns to normal and further control is prohibited.

      • When normal control is complete, brake hold control is prohibited.

      When control is not being performed:


      • Control will not be started.

      • ABS warning light illuminates.

      • SLIP indicator illuminates.

      • Brake hold operated indicator light blinks.

      U0073

      U0124

      (Skid control ECU (brake actuator assembly))

      When control is being performed:


      • A message is displayed on the multi-information display and brake hold control is canceled when the brake pedal is depressed.

      When control is not being performed:


      • Control will not be started.

      • SLIP indicator illuminates.

      • Brake hold operated indicator light blinks.

      U0100

      (Skid control ECU (brake actuator assembly))

      Eco Run Hill-assist Control


      • Maintains the brake fluid pressure for up to 2 seconds and gradually releases the brake fluid pressure over 1 second when the accelerator pedal is depressed after the engine is stopped by the stop and start system when the vehicle is stopped.

      		 Skid control ECU (brake actuator assembly)

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • ECM

      • Steering sensor

      • Engine stop and start ECU

      When control is being performed:


      • When back-up control (vehicle behavior stabilization) is complete, braking returns to normal and further control is prohibited.

      • When normal control is complete, brake hold control is prohibited.

      When control is not being performed:


      • Control will not be started.

      • Brake warning light illuminates.

      • ABS warning light illuminates.

      • SLIP indicator illuminates.

      • Brake hold operated indicator light blinks.

      U0073

      U0100

      U0124

      U0126

      (Skid control ECU (brake actuator assembly))

      Headlight Leveling Control (Headlight Control)


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

      		 Headlight ECU sub-assembly LH

      • Skid control ECU (brake actuator assembly)

      • Main body ECU (multiplex network body ECU)

      • ECM (for Triple Beam Headlight)

      		 Headlight Leveling Control is stopped. -

      U0100 (for Triple Beam Headlight)

      U0129

      U0142

      (Headlight ECU sub-assembly LH)

      Cornering Light


      • Turns the cornering light on and off according to the wheel speed, turn, steering angle and shift position data.

      		 Headlight ECU sub-assembly LH

      • Main body ECU (multiplex network body ECU)

      • Skid control ECU (brake actuator assembly)

      • Combination meter assembly

      • ECM

      • Steering sensor

      		 Cornering light Control is stopped. -

      U0101

      U0126

      U0129

      U0142

      U0155

      (Headlight ECU sub-assembly LH)

      Low Beam, High Beam


      • Turns the specified light source on and off according to low beam, high beam command data.

      		 Main body ECU (multiplex network body ECU) Headlight ECU sub-assembly LH Forces the low beams to illuminate. -

      U0073

      U0142

      U1000

      (Headlight ECU sub-assembly LH)
      Adaptive High Beam System Headlight ECU sub-assembly LH

      • Main body ECU (multiplex network body ECU)

      • Skid control ECU (brake actuator assembly)

      • ECM

      • Steering sensor

      • Forward recognition camera

      		 Operation of the high beams is prohibited while operation of the low beams continue as normal. -

      U0101

      U0126

      U0129

      U0142

      U023A

      (Headlight ECU sub-assembly LH)

      AVS Control


      • Controls the variable damping force according to road and driving conditions.

      		 Absorber control ECU

      • ECM

      • Skid control ECU (brake actuator assembly)

      • Steering sensor

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • Engine stop and start ECU

      • Continues to control the damping force.

      • Interrupts damping force control after moving front absorber control actuators and rear absorber control actuators to the 9th step.

      • Controls other than the anti-roll control and the anti-squat control are maintained.

      • Control is maintained in "medium" mode.

      • Controls for when the stop and start system is on are performed.

      		 -

      U0100

      U0122

      U0124

      U0126

      U1103

      (Absorber control ECU)

      Air Conditioning Control


      • Controls air conditioning functions such as set temperature adjustment, air outlet selection, etc. by operating LEXUS display audio controller or Remote Touch.

      		 Radio receiver assembly Air conditioning amplifier assembly

      • Air conditioning system indicators turn off.

      • If set temperature is shown on multi-information display or multi-display, set temperature display turns off.

      		 Displays messages on the multi-information display.

      U0073

      U0164

      (Radio receiver assembly)

      LEXUS Parking Assist-sensor System Setting/Notification


      • Controls settings for clearance sonar screen notifications which are set by operating Remote Touch, displays sonar status and plays voice warnings.

      		 Radio receiver assembly

      • ECM

      • Clearance warning ECU assembly

      • If a communication stop occurs while the clearance sonar settings screen is displayed, the settings screen is cleared.

      • If a communication stop occurs while the clearance sonar sensor screen is displayed, the sensor screen is cleared.

      		 -

      U0073

      U0100

      U1110

      (Radio receiver assembly)

      Fuel Consumption Display


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

      		 Radio receiver assembly

      • ECM

      • Combination meter assembly

      • Skid control ECU (brake actuator assembly)

      When communication with ECM or skid control ECU is interrupted:


      • Display is not updated.

      When communication with combination meter is interrupted:


      • Depending on the interrupted signal, the instantaneous fuel economy, average speed, elapsed time (after start) or drivable mileage is not displayed.

      • Numeric part of driveable mileage is cleared.

      		 -

      U0100

      U0129

      U0155

      (Radio receiver assembly)

      Destination Identification


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

      		 Radio 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). Time zone and language selection screen are different from actual destination.

      U0140

      (Radio receiver assembly)

      Tire Pressure Monitoring System


      • Receives information from TPMS ECU to display air pressure, tire location and system status.

      		 Main body ECU (multiplex network body ECU)

      • Main body ECU (multiplex network body ECU)

      • Radio receiver assembly

      • When the current tire pressure screen is not displayed: The switch to enter the current tire pressure screen is grayed out.

      • When the current tire pressure screen is displayed: The tire pressure values are not displayed.

      		 -

      U0073

      (Radio receiver assembly)

      Power Tilt and Power Telescopic Steering Column Control


      • Starts steering wheel auto return or auto away based on an engine switch on/off signal or equivalent.

      • Memorizes and recalls selected driving position according to memory switch operation.

      • Moves steering wheel to selected position according to manual switch operation on steering column cover.

      		 Multiplex tilt and telescopic ECU

      • Combination meter assembly

      • Main body ECU (multiplex network body ECU)

      • Position control ECU and switch assembly LH (for LHD)

      • Position control ECU and switch assembly RH (for RHD)

      • Driving position memory function is prohibited.

      • Auto away/return function is prohibited.

      		 -

      U0142

      U0208

      (Multiplex tilt and telescopic ECU)

      Seat Position Memory System


      • Controls the seat position based on operation conditions.

      • Position control ECU and switch assembly LH (for LHD)

      • Position control ECU and switch assembly RH (for RHD)

      • Main body ECU (multiplex network body ECU)

      • ECM

      • Combination meter assembly

      • Multiplex tilt and telescopic ECU

      		 Controls the seat position based on operation conditions. - -
      Mirror Surface Adjustment

      • Outer mirror control ECU assembly (for driver side)

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

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

      • Outer mirror control ECU assembly (for driver side)

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

      • Main body ECU (multiplex network body ECU)

      • Air conditioning amplifier assembly

      		 Mirror heaters do not operate. -

      U0142

      (Outer mirror control ECU assembly)

      Mirror Retract/Return Operation


      • Controls retract/return operation of the outer mirrors based on signals such as mirror switch signal from main body ECU.

      • Outer mirror control ECU assembly (for driver side)

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

      		 Main body ECU (multiplex network body ECU) Mirrors cannot be retracted or returned. -

      U0142

      (Outer mirror control ECU assembly)
      Reverse-shift Linked Door Mirror Operation

      • Outer mirror control ECU assembly (for driver side)

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

      		 Main body ECU (multiplex network body ECU) Reverse-shift linked door mirror function does not operate. - -
      Mirror Surface Position Memory and Recall

      • Outer mirror control ECU assembly (for driver side)

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

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

      Illumination Control


      • Controls illumination of lights based on courtesy switch information and interior light information.

      • Outer mirror control ECU assembly (for driver side)

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

      		 Main body ECU (multiplex network body ECU) Mirror foot illumination is turned off. -

      U0142

      (Outer mirror control ECU assembly)

      Seat Memory Switch Signal Forwarding


      • Transmits memory switch signal via the CAN bus.

      		 Main body ECU (multiplex network body ECU)

      • Outer mirror control ECU assembly (for driver side)

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

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

      Dynamic Radar Cruise Control System


      • Accelerates or decelerates the vehicle to maintain the distance to the vehicle ahead.

      		 ECM

      • Skid control ECU (brake actuator assembly)

      • Driving support ECU assembly

      		 Control stops. Displays messages on the multi-information display.

      U010087

      U012287

      U110487

      (ECM)

      Dynamic Radar Cruise Control System


      • Accelerates or decelerates the vehicle to maintain the distance to the vehicle ahead.

      		 Driving support ECU assembly

      • ECM

      • Skid control ECU (brake actuator assembly)

      • Steering sensor

      • Millimeter wave radar sensor assembly

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      		 - Displays messages on the multi-information display.

      U0100

      U0125

      U0126

      U0129

      U0235

      (Driving support ECU assembly)

      Pre-crash Safety System


      • Controls the brakes immediately before a crash.

      		 Driving support ECU assembly

      • Millimeter wave radar sensor assembly

      • Forward recognition camera

      • Skid control ECU (brake actuator assembly)

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly

      • Steering sensor

      • ECM

      • Main body ECU (multiplex network body ECU)

      • Combination meter assembly

      		 Control stops.

      • Displays messages on the multi-information display.

      • PCS indicator light flashes.

      U0100

      U0125

      U0126

      U0129

      U1104

      (Driving support ECU assembly)

      LEXUS Parking Assist-sensor System Control


      • Judges vehicle speed.

      		 Clearance warning ECU assembly Skid control ECU (brake actuator assembly) Clearance sonar detection will be operated based on a vehicle speed of 20 km/h or more. - -

      Mute Switch Judgment


      • Changes the clearance sonar system settings when the mute switch is operated.

      		 Clearance warning ECU assembly Combination meter assembly Control operates with the latest setting. -

      U0155

      (Clearance warning ECU assembly)

      Lane Keeping Assist System / Lane Departure Alert System


      • Warns when vehicle is deviating from its lane.

      		 Forward recognition camera

      • Skid control ECU (brake actuator assembly)

      • Steering sensor

      • Main body ECU (multiplex network body ECU)

      • Power steering ECU assembly

      • Combination meter assembly

      • ECM

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • Driving support ECU assembly

      • Millimeter wave radar sensor assembly

      		 Control stops. Displays messages on the multi-information display.

      U0100

      U0101

      U0123

      U0126

      U0129

      U0131

      U0142

      U0155

      U1104

      (Forward recognition camera)

      Road Sign Assist Function


      • Identifies road signs while driving and displays them on the multi-information display.

      		 Forward recognition camera

      • ECM

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • Skid control ECU (brake actuator assembly)

      • Main body ECU (multiplex network body ECU)

      • Combination meter assembly

      		 Road sign assist function is canceled. Displays messages on the multi-information display.

      U0100

      U0101

      U0123

      U0129

      U0142

      U0155

      (Forward recognition camera)

      Blind Spot Monitor Control


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

      		 Blind spot monitor sensor LH

      • Skid control ECU (brake actuator assembly)

      • Steering sensor

      • Main body ECU (multiplex network body ECU)

      • ECM

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      		 - Displays messages on the multi-information display.

      U0100

      U0125

      U0126

      U0129

      U0142

      (Blind spot monitor sensor LH)

      Parking Assist Monitor without Parallel Parking Assist Function


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

      		 Rear television camera assembly

      • Main body ECU (multiplex network body ECU)

      • Steering sensor

      • Skid control ECU (brake actuator assembly)

      • ECM

      • Radio receiver assembly

      • Power steering ECU assembly

      • Clearance warning ECU assembly

      		 Parking assist monitor function is prohibited.

      • Predicted path guide lines are not displayed.

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

      U0100

      U0126

      U0140

      U0163

      U1110

      (Rear television camera assembly)

      Auto Location


      • Displays the location and pressure value of all tires on the combination meter assembly.

      		 Tire pressure warning ECU and receiver Skid control ECU (brake actuator assembly) Auto Location function is prohibited. -

      U0129

      (Tire pressure warning ECU and receiver)

      Panoramic View Monitor


      • Displays the bird's-eye view, back view, side view and front view of the vehicle on the multi-information display.

      • Displays guide lines on the panoramic view monitor screen.

      • Displays the detection area of the clearance sonar sensor.

      		 Parking assist ECU

      • Steering sensor

      • Skid control ECU (brake actuator assembly)

      • Main body ECU (multiplex network body ECU)

      • ECM

      • Clearance warning ECU assembly

      • Blind spot monitor sensor LH

      • Radio receiver assembly

      • Rear television camera assembly

      • Front television camera assembly

      • Side camera RH (outer rear view mirror assembly RH)

      • Side camera LH (outer rear view mirror assembly LH)

      		 Panoramic view monitor system does not operate. -

      U0073

      U0100

      U0126

      U0129

      U0140

      U0163

      U0233

      U0265

      U0266

      U0267

      U0268

      U1110

      (Parking assist ECU)

      ATC-4WD System


      • Controls drive force of the front and rear wheels in accordance with the driving conditions.

      		 4WD ECU assembly

      • ECM

      • Steering sensor

      • Skid control ECU (brake actuator assembly)

      • Yaw rate sensor assembly (w/ TFT Meter Type Combination Meter Assembly)

      • Airbag sensor assembly (w/ Optitron Meter Type Combination Meter Assembly)

      • Main body ECU (multiplex network body ECU)

      • Air conditioning amplifier assembly

      Depending on the malfunctioning communication line, any of the following controls are performed.


      • Control is prohibited.

      • Control is maintained using the latest value received from the yaw rate sensor assembly.

      • Control is maintained using the latest value received from the skid control ECU (brake actuator assembly).

      • Control is maintained using the latest value received from the ECU or sensor.

      		 Displays messages on the multi-information display.

      U0073

      U0100

      U0126

      U0129

      (4WD ECU assembly)
      Headup Display (Tachometer) Combination meter mirror ECU (headup display) ECM The tachometer in the headup display shows that the engine speed is 0 rpm. -

      U0100

      (Combination meter mirror ECU (headup display))
      Headup Display (Pre-crash System) Combination meter mirror ECU (headup display) Driving support ECU assembly The pre-crash safety indicator light in the headup display keeps indicating the latest condition. -

      U1104

      (Combination meter mirror ECU (headup display))
      Headup Display (LKA/LDA System) Combination meter mirror ECU (headup display) Forward recognition camera Lane markers are not displayed. -

      U023A

      (Combination meter mirror ECU (headup display))

      Driver seat switch operation function


      • Opens/closes the power back door when the driver seat switch is operated.

      		 Multiplex network door ECU

      • Main body ECU (multiplex network body ECU)

      • ECM

      • Combination meter assembly

      • Power back door opening operation is canceled and a buzzer sounds.

      • Power back door opening/closing operation does not operate.

      		 -

      U0101

      U0142

      U0155

      (Multiplex network door ECU)

      Wireless switch operation


      • Opens/closes the power back door and operates the wireless one motion by wireless switch operation.

      		 Multiplex network door ECU

      • Main body ECU (multiplex network body ECU)

      • Certification ECU (smart key ECU assembly)

      • Power back door automatic open/close does not operate.

      • Wireless one motion does not operate and a buzzer sounds.

      		 -

      U0142

      U0327

      (Multiplex network door ECU)

      Back door handle operation


      • Opens the power back door when the back door handle is operated.

      		 Multiplex network door ECU Main body ECU (multiplex network body ECU) Power back door open does not operate. -

      U0142

      (Multiplex network door ECU)

      Touchless power back door operation


      • Opens the power back door when the rear emblem sensor detects a hand.

      		 Multiplex network door ECU Main body ECU (multiplex network body ECU) Power back door automatic open/close does not operate. -

      U0142

      (Multiplex network door ECU)