Tech Tips
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. Replace parts as necessary.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.
| Symptom | Suspected Area | See page |
|---|---|---|
| Lane departure alert system (w/ steering control) does not operate | Forward recognition camera power source circuit | |
| Steering pad switch circuit | ||
| CAN communication system | ||
| Forward recognition camera | ||
| Lane departure alert indicator abnormal (Does not turn on) | Lane departure alert indicator circuit | |
| Steering pad switch circuit | ||
| CAN communication system | ||
| Combination meter assembly | ||
| Forward recognition camera | ||
| Lane departure alert indicator abnormal (Remains on) | Lane departure alert indicator circuit | |
| Lane departure alert main switch circuit | ||
| CAN communication system | ||
| Combination meter assembly | ||
| Forward recognition camera | ||
| 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) |
|
| Turn signal light switch circuit | ||
| Forward recognition camera | ||
| Increase in cases that driver can see line 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 | ||
| Forward recognition camera | ||
| 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) |
|
| Combination meter assembly | ||
| Forward recognition camera | ||
| Buzzer does not sound even when lane markers are lost while lane departure warning function is operating | Combination meter assembly | |
| Forward recognition camera |