Problem Symptoms Table [11/2017 - 03/2019]

HINT:

If any of the following symptoms exist despite the normal system code being output when checking for CAN communication and lane departure alert system (w/ Steering Control) DTCs, check the suspected areas in the order they are listed.
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.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.

LANE DEPARTURE ALERT SYSTEM (W/ STEERING CONTROL)

Symptom	Suspected Area	Link
Lane departure alert system (w/ Steering Control) does not operate	Power source circuit	Refer to Power Source Circuit [11/2017 - 01/2023]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [11/2017 - 01/2023]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
The lane departure alert indicator does not illuminate even when the lane departure alert main switch is operated.	Indicator circuit	Refer to Indicator Circuit [11/2017 - 01/2023]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [11/2017 - 01/2023]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019]
	Combination meter assembly	Refer to REMOVAL [09/2014 - ]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
	Driving support ECU assembly	Refer to REMOVAL [09/2014 - 01/2023]
The lane departure alert indicator does not turn off even when the lane departure alert main switch is operated.	Indicator circuit	Refer to Indicator Circuit [11/2017 - 01/2023]
	Steering pad switch circuit	Refer to Steering Pad Switch Circuit [11/2017 - 01/2023]
	CAN communication system	Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019]
	Combination meter assembly	Refer to REMOVAL [09/2014 - ]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
Lane departure alert system (w/ Steering Control) is not canceled even when turn signal light switch is operated	Data List/Active Test (Check turn signal switch signal)	Refer to DATA LIST / ACTIVE TEST [11/2017 - 01/2023]
	Turn signal switch circuit (for Triple Beam Headlight)	Refer to Turn Signal Switch Circuit [09/2014 - 03/2019]
	Turn signal switch circuit (for Single Beam Headlight)	Refer to Turn Signal Switch Circuit [09/2014 - 03/2019]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
Increase in cases that driver can see lane markers but system cannot detect lane markers	Windshield glass is dirty	-
	Forward recognition camera is dirty	-
	Headlight assemblies are dirty or worn	-
	Non-standard suspension is installed	-
	Non-standard tires are installed	-
	Non-Lexus genuine windshield glass is installed	-
	There is a foreign object or foreign matter between the windshield glass and forward recognition camera	-
	A sticker or similar item is attached to the area in front of the forward recognition camera	-
	Adjust forward recognition camera	Refer to ADJUSTMENT (SEQUENTIAL RECOGNITION) [11/2017 - 01/2023]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
Lane departure alert system (w/ Steering Control) is operating, but no operation condition is displayed on multi-information display in combination meter assembly	Data List/Active Test (Check the item LDA Control)	Refer to DATA LIST / ACTIVE TEST [11/2017 - 01/2023]
	Combination meter assembly	Refer to REMOVAL [09/2014 - ]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]
Buzzer does not sound even when vehicle deviates from its lane.	Combination meter assembly	Refer to REMOVAL [09/2014 - ]
	Forward recognition camera	Refer to REMOVAL [11/2017 - 01/2023]