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Home >> Toyota >> 2012 >> Prius Three >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Lane Keeping Assist System (Except Plug-In)(Diagnostics - Introduction) >> Lane-Keeping Assist System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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LANE-KEEPING ASSIST SYSTEM

Symptom Suspected Area See
Lane-keeping assist system does not operate Main switch circuit Refer to Main Switch Circuit
Lane-recognition camera sensor assembly Refer to REMOVAL
Harness and connector -
Driving support ECU Refer to REMOVAL
LKA indicator light is abnormal (Does not turn on) Indicator light circuit Refer to Indicator Circuit
Main switch circuit Refer to Main Switch Circuit
Combination meter Refer to PROBLEM SYMPTOMS TABLE
Driving support ECU Refer to REMOVAL
LKA indicator light is abnormal (Remains on) Indicator light circuit Refer to Indicator Circuit
Main switch circuit Refer to Main Switch Circuit
Combination meter Refer to PROBLEM SYMPTOMS TABLE
Driving support ECU Refer to REMOVAL
Lane-keeping assist system is not canceled even when turn signal light switch is operated Turn signal light switch Refer to INSPECTION
Harness or connector -
Driving support ECU Refer to REMOVAL
Lane-keeping assist system is not canceled even when windshield wiper switch is operated (Lo or Hi) Windshield wiper switch Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Harness or connector -
Driving support ECU Refer to REMOVAL
Increase in cases that driver can see line marker but system cannot detect lane markers Windshield glass is dirty -
Lane recognition camera sensor is dirty -
Adjust object recognition camera sensor Refer to ADJUSTMENT
Driving support ECU Refer to REMOVAL
Lane-keeping assist system is operating, but no operation condition is displayed on multi-information display in combination meter Combination meter Refer to PROBLEM SYMPTOMS TABLE
Driving support ECU Refer to REMOVAL
Buzzer does not sound even when lane markers are lost during lane departure warning function Skid control buzzer Refer to DTC C1A4A: Skid Control Buzzer Circuit
Brake booster with master cylinder (skid control ECU) Refer to REMOVAL
Driving support ECU Refer to REMOVAL
Lane-keeping assist system cannot detect line marker during nighttime Headlight Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Driving support ECU Refer to REMOVAL