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Home >> Lexus >> 2012 >> LS 460 RWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Cruise Control Systems >> Dynamic Radar Cruise Control System (Diagnostics - Introduction) >> Dynamic Radar Cruise Control System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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DYNAMIC RADAR CRUISE CONTROL SYSTEM

Symptom Suspected Area Reference
Main switch cannot be turned ON (CRUISE main indicator light combination meter does not illuminate) Cruise control switch circuit Refer to Cruise Control Switch Circuit
CRUISE main indicator light circuit Refer to Cruise Main Indicator Light Circuit
Driving support ECU Refer to COMPONENTS
Vehicle speed setting cannot be done (CRUISE main indicator light on combination meter illuminates when main switch is turned ON, but turns off when operating SET function) Cruise control switch circuit Refer to Cruise Control Switch Circuit
Driving support ECU Refer to COMPONENTS
Vehicle speed setting cannot be done (CRUISE main indicator light on combination meter illuminates when main switch is turned ON and remains illuminated when operating SET function) Cruise control switch circuit Refer to Cruise Control Switch Circuit
Stop light switch circuit Refer to DTC C1A05: Stop Light Switch Circuit
Park/neutral position switch Refer to INSPECTION
Transmission control switch circuit Refer to Transmission Control Switch Circuit
Shift paddle switch circuit (w/ Shift Paddle Switch) Refer to Shift Paddle Switch Circuit
Combination meter Refer to COMPONENTS
Driving support ECU Refer to COMPONENTS
While vehicle is driven with cruise control, set control is cancel (CRUISE main indicator light remains illuminated) Cruise control switch circuit Refer to Cruise Control Switch Circuit
Skid control ECU Refer to REMOVAL
CAN communication system Refer to PRECAUTION
Stop light switch circuit Refer to DTC C1A05: Stop Light Switch Circuit
CRUISE main indicator light circuit Refer to Cruise Main Indicator Light Circuit
Park/neutral position switch Refer to INSPECTION
Driving support ECU Refer to COMPONENTS
Hunting (Speed is not constant) Skid control ECU Refer to REMOVAL
CAN communication system Refer to PRECAUTION
Speedometer malfunction Refer to Speedometer Malfunction
Front millimeter wave radar sensor power source circuit Refer to Millimeter Wave Radar Sensor Power Source Circuit
Driving support ECU power source circuit Refer to ECU Power Source Circuit
Driving support ECU Refer to COMPONENTS
Vehicle speed setting cannot be canceled (When Coast, Acceleration, Resume, Set speed change and control switch are operated) Cruise control switch circuit Refer to Cruise Control Switch Circuit
Driving support ECU Refer to COMPONENTS
Erroneous detection or lost sight of vehicle in front Clean radar sensor with soft cloth, etc. -
Improper aiming of sensor beam axis -
Warning buzzer does not sound Warning buzzer Refer to DTC C1A4A: Skid Control Buzzer Circuit
Electronically control brake system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Front millimeter wave radar sensor power source circuit Refer to Millimeter Wave Radar Sensor Power Source Circuit
Driving support ECU power source circuit Refer to ECU Power Source Circuit
Driving support ECU Refer to COMPONENTS
Set distance cannot be changed Distance control switch circuit Refer to Distance Control Switch Circuit
CAN communication system Refer to PRECAUTION
Driving support ECU Refer to COMPONENTS
No display Meter / gauge system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
CAN communication system Refer to PRECAUTION
Driving support ECU Refer to COMPONENTS
No brake control (when decelerating) Electronically control brake system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Driving support ECU power source circuit Refer to ECU Power Source Circuit
CAN communication system Refer to PRECAUTION
Driving support ECU Refer to COMPONENTS
Constant speed control mode cannot be turned on Cruise control switch circuit Refer to Cruise Control Switch Circuit
Meter / gauge system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Vehicle speed cannot be canceled with wiper HI (Including automatic wiper) Windshield wiper switch Refer to COMPONENTS
Driving support ECU Refer to COMPONENTS
Unable to adjust beam axis of front millimeter wave radar sensor Check for DTC C1A10 Refer to DTC C1A10: Front Radar Sensor
Check position, distance and angle of reflector -
Check installation of front millimeter wave radar sensor -
Front millimeter wave radar sensor Refer to COMPONENTS
Driving support ECU Refer to COMPONENTS
System cannot change between constant speed control mode and vehicle-to-vehicle distance control mode Cruise control switch circuit Refer to Cruise Control Switch Circuit
Driving support ECU Refer to COMPONENTS