Problem Symptoms Table [05/2023 - ]

WARNING: This page is about a different car, the 2024 Lexus LC 500. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Before replacing the ECM, refer to Registration.
When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the millimeter wave radar sensor assembly will not match the information from the vehicle and a DTC may be stored.
When the millimeter wave radar sensor assembly has been replaced with a new one, it is necessary to perform millimeter wave radar sensor assembly beam axis alignment and to clear the vehicle control history (RoB). Before performing the Driving Adjustment, make sure to read Before Starting Driving Adjustment.
HINT:

Beam axis alignment of the millimeter wave radar sensor assembly can be performed using either Triangle Target, Flat Surface Target or Driving Adjustment.

Triangle Target: Refer to TARGET ADJUSTMENT (TRIANGLE TARGET) [05/2023 - ]

Flat Surface Target: Refer to TARGET ADJUSTMENT (FLAT SURFACE TARGET) [05/2023 - ]

Driving Adjustment: Refer to DRIVING ADJUSTMENT [05/2023 - ]
When replacing the forward recognition camera, replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle and a DTC may be stored.
When the forward recognition camera is replaced with a new one or the windshield glass is replaced or removed/installed, make sure to read Before Starting Adjustment, then perform optical axis alignment for the forward recognition camera and clear the vehicle control history (RoB) for each system.
HINT:

Forward recognition camera axis alignment can be performed by using either One Time Recognition, Sequential Recognition or Driving Adjustment.

One Time Recognition: Refer to TARGET ADJUSTMENT (ONE TIME RECOGNITION) [05/2023 - ]

Sequential Recognition: Refer to TARGET ADJUSTMENT (SEQUENTIAL RECOGNITION) [05/2023 - ]

Driving Adjustment: Refer to DRIVING ADJUSTMENT [05/2023 - ]

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.
Determine the problem symptoms, then perform the respective inspection procedures.
By using the vehicle control history (RoB), various control parameter history can be checked.

DYNAMIC RADAR CRUISE CONTROL SYSTEM

Symptom	Suspected Area	Link
The dynamic radar cruise control system cannot be turned on using the cruise control main switch	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	Cruise main indicator light circuit	Refer to Cruise Main Indicator Light Circuit [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
The dynamic radar cruise control mode cannot be changed between vehicle-to-vehicle distance control mode and constant speed control mode	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Distance Control Switch Circuit [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
The vehicle-to-vehicle distance cannot be changed	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Distance control switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
Vehicle speed setting cannot be performed (in constant speed control mode)	Fail-safe chart	Refer to FAIL-SAFE CHART [05/2023 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	Stop light switch circuit	Refer to DTC P0571: Stop Light Switch Circuit Malfunction [05/2023 - ]
	SFI system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Vehicle speed setting cannot be performed (in vehicle-to-vehicle distance control mode)	Front Radar Sensor Temporary Unavailable (Optical Axis Misalignment) history	Refer to VEHICLE CONTROL HISTORY (RoB) [05/2023 - ]
	Fail-safe chart	Refer to FAIL-SAFE CHART [05/2023 - ]
	Forward recognition camera is temporarily unavailable	Refer to FAIL-SAFE CHART [05/2023 - ]
	Millimeter wave radar sensor assembly is dirty	Refer to FAIL-SAFE CHART [05/2023 - ]
	Millimeter wave radar sensor assembly beam axis not adjusted HINT: Beam axis alignment of the millimeter wave radar sensor assembly can be performed using either Triangle Target, Flat Surface Target or Driving Adjustment.	Triangle Target: Refer to TARGET ADJUSTMENT (TRIANGLE TARGET) [05/2023 - ] Flat Surface Target: Refer to TARGET ADJUSTMENT (FLAT SURFACE TARGET) [05/2023 - ] Driving Adjustment: Refer to DRIVING ADJUSTMENT [05/2023 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	SFI system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electric parking brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Millimeter wave radar sensor assembly	Refer to REMOVAL [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Control of vehicle speed by the dynamic radar cruise control system is canceled (in constant speed control mode)	Fail-safe chart	Refer to FAIL-SAFE CHART [05/2023 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	Stop light switch circuit	Refer to DTC P0571: Stop Light Switch Circuit Malfunction [05/2023 - ]
	SFI system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Control of vehicle speed by the dynamic radar cruise control system is canceled (in vehicle-to-vehicle distance control mode)	Fail-safe chart	Refer to FAIL-SAFE CHART [05/2023 - ]
	Forward recognition camera is temporarily unavailable	Refer to FAIL-SAFE CHART [05/2023 - ]
	Millimeter wave radar sensor assembly is dirty	Refer to FAIL-SAFE CHART [05/2023 - ]
	Millimeter wave radar sensor assembly beam axis not adjusted HINT: Beam axis alignment of the millimeter wave radar sensor assembly can be performed using either Triangle Target, Flat Surface Target or Driving Adjustment.	Triangle Target: Refer to TARGET ADJUSTMENT (TRIANGLE TARGET) [05/2023 - ] Flat Surface Target: Refer to TARGET ADJUSTMENT (FLAT SURFACE TARGET) [05/2023 - ] Driving Adjustment: Refer to DRIVING ADJUSTMENT [05/2023 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	SFI system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electric parking brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Millimeter wave radar sensor assembly	Refer to REMOVAL [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Hunting/vehicle speed is not constant (in constant speed control mode)	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Hunting/vehicle speed is not constant (in vehicle-to-vehicle distance control mode)	Millimeter wave radar sensor assembly is dirty	Refer to FAIL-SAFE CHART [05/2023 - ]
	Millimeter wave radar sensor assembly beam axis not adjusted HINT: Beam axis alignment of the millimeter wave radar sensor assembly can be performed using either Triangle Target, Flat Surface Target or Driving Adjustment.	Triangle Target: Refer to TARGET ADJUSTMENT (TRIANGLE TARGET) [05/2023 - ] Flat Surface Target: Refer to TARGET ADJUSTMENT (FLAT SURFACE TARGET) [05/2023 - ] Driving Adjustment: Refer to DRIVING ADJUSTMENT [05/2023 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Millimeter wave radar sensor assembly	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Vehicle speed control by the dynamic radar cruise control system is not canceled when the CANCEL switch is pushed	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Depressing the brake pedal does not cancel control of vehicle speed by the dynamic radar cruise control system	Stop light switch circuit	Refer to DTC P0571: Stop Light Switch Circuit Malfunction [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Control cannot be canceled while the vehicle is stopped	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Electric parking brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Seat belt warning system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Door courtesy switch circuit	Refer to Door Courtesy Switch Circuit [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Control cannot be canceled by operating the parking brake	Electric parking brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Skid control ECU assembly	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Even though the millimeter wave radar sensor assembly and forward recognition camera are not dirty, the warning message "Radar Cruise Control Unavailable See Owner's Manual" is displayed	Millimeter wave radar sensor assembly	Refer to REMOVAL [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
The vehicle approach warning buzzer does not sound	Meter/gauge system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	Check millimeter wave radar sensor assembly installation position	Refer to INSTALLATION [05/2023 - ]
	Check installation of forward recognition camera	Refer to INSTALLATION [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	Millimeter wave radar sensor assembly	Refer to REMOVAL [05/2023 - ]
Even though the vehicle approach warning buzzer is sounding, brake control is not performed to decelerate the vehicle	Electronically controlled brake system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [07/2020 - ]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Even though the SET function is operating, the cruise SET indicator does not illuminate	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Cruise SET indicator light circuit	Refer to Cruise SET Indicator Light Circuit [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
The cruise control indicator remains illuminated	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Cruise main indicator light circuit	Refer to Cruise Main Indicator Light Circuit [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
Indicators are not displayed on the multi-information display in the combination meter assembly	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
A buzzer does not sound when control of vehicle speed by the dynamic radar cruise control is canceled	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	ECM	Refer to REMOVAL [05/2023 - ]
The dynamic radar cruise control system operates normally but the curve speed reduction function does not operate	Customize parameters	Refer to CUSTOMIZE PARAMETERS [05/2023 - ]
	Front camera system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ]
	Forward recognition camera	Refer to REMOVAL [05/2023 - ]