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Problem Symptoms Table

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DYNAMIC RADAR CRUISE CONTROL SYSTEM

Symptom Suspected Area See
Main switch cannot be turned ON. (Cruise main indicator light on 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
ECM Refer to TERMINALS OF ECU 
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
ECM Refer to TERMINALS OF ECU 
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 P0571: Brake Switch "A" Circuit
Park / Neutral position switch circuit (for AA80E) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
Park / Neutral position switch circuit (for A760E) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
Park / Neutral position switch circuit (for A760H) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
Transmission control switch circuit (for AA80E) Refer to Transmission Control Switch Circuit
Transmission control switch circuit (for A760E) Refer to Transmission Control Switch Circuit
Transmission control switch circuit (for A760H) Refer to Transmission Control Switch Circuit
Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECU 
While the vehicle is driven with cruise control, the set control is canceled. (Cruise main indicator light remains illuminated.) Cruise control switch circuit Refer to Cruise Control Switch Circuit
Vehicle speed sensor circuit Refer to DTC P0500: Vehicle Speed Sensor Malfunction; DTC P0503: Vehicle Speed Sensor "A" Intermittent / Erratic / High
Stop light switch circuit Refer to DTC P0571: Brake Switch "A" Circuit
Cruise main indicator light circuit Refer to Cruise Main Indicator Light Circuit
Park / Neutral position switch circuit (for AA80E) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
Park / Neutral position switch circuit (for A760E) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
Park / Neutral position switch circuit (for A760H) Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
ECM Refer to TERMINALS OF ECU 
Hunting (Speed is not constant.) Vehicle speed sensor circuit Refer to DTC P0500: Vehicle Speed Sensor Malfunction; DTC P0503: Vehicle Speed Sensor "A" Intermittent / Erratic / High
SFI system  
ECM Refer to TERMINALS OF ECU 
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
ECM Refer to TERMINALS OF ECU 
Erroneous detection or lost sight of the vehicle ahead. Clean laser sensor with soft cloth, etc. -
Improper aiming of sensor beam axis Refer to ADJUSTMENT
Alarm buzzer does not sound. Buzzer circuit Refer to Skid Control Buzzer Circuit
VSC system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Millimeter wave radar sensor power source circuit Refer to Millimeter Wave Radar Sensor Power Source Circuit
Distance control ECU power source circuit Refer to Distance Control ECU Power Source Circuit
Distance control ECU Refer to TERMINALS OF ECU 
ECM Refer to TERMINALS OF ECU 
Set distance cannot be changed. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Distance control switch Refer to Distance Control Switch Circuit
Cruise control switch circuit Refer to Cruise Control Switch Circuit
ECM Refer to TERMINALS OF ECU 
No display Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECU 
No brake control (when decelerating) VSC system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Distance control ECU power source circuit Refer to Distance Control ECU Power Source Circuit
Distance control ECU Refer to TERMINALS OF ECU 
ECM Refer to TERMINALS OF ECU 
Constant speed mode cannot be turned on. Cruise control switch circuit Refer to Cruise Control Switch Circuit
Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECU 
Vehicle speed cannot be canceled with wiper HI. (Including automatic wiper) Rain sensor system Refer to Rain Sensor Circuit
Wiper signal circuit Refer to Wiper Switch (HI Speed) Circuit
Distance control ECU Refer to TERMINALS OF ECU
ECM Refer to TERMINALS OF ECU
Setting cannot be canceled in SNOW mode. Pattern select switch circuit (for AA80E) Refer to Pattern Select Switch Snow Mode Circuit
Pattern select switch circuit (for A760E) Refer to Pattern Select Switch Snow Mode Circuit
Pattern select switch circuit (for A760H) Refer to Pattern Select Switch Snow Mode Circuit
Automatic transmission system (for AA80E) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Automatic transmission system (for A760E) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Automatic transmission system (for A760H) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECU 
Unable to adjust (complete) beam axis of millimeter wave radar sensor. Check for DTC P1570 Refer to DTC P1570: Radar Sensor Malfunction
Check position, distance and angle of reflector Refer to ADJUSTMENT
Check installation of millimeter wave radar sensor -
Millimeter wave radar sensor Refer to REMOVAL
Distance control ECU Refer to TERMINALS OF ECU 
ECM Refer to TERMINALS OF ECU 
Cannot change between constant speed control mode and vehicle-to-vehicle distance control mode Cruise control switch circuit Refer to Cruise Control Switch Circuit
ECM Refer to TERMINALS OF ECU