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Problem Symptoms Table

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Dynamic Radar Cruise Control System 

SYMPTOM CHART

Symptom Suspected Area See
Main switch cannot be turned ON. (CRUISE main indicator light on combination meter does not illuminate.) 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. CRUISE main indicator light circuit CRUISE MAIN INDICATOR LIGHT CIRCUIT 
3. ECM 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.) 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. ECM 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.) 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. Stop light switch circuit DTC P0571 Brake Switch "A" Circuit 
3. Park / Neutral position switch circuit (for AA80E) MONITOR DESCRIPTION
3. Park / Neutral position switch circuit (for A760E) DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
3. Park / Neutral position switch circuit (for A760H) DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
4. Transmission control switch circuit (for AA80E) AUTOMATIC TRANSMISSION UNIT
4. Transmission control switch circuit (for A760E) TRANSMISSION CONTROL SWITCH CIRCUIT
4. Transmission control switch circuit (for A760H) TRANSMISSION CONTROL SWITCH CIRCUIT
5. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
6. ECM TERMINALS OF ECU 
While the vehicle is driven with cruise control, the set control is canceled. (CRUISE main indicator light remains illuminated.) 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. Vehicle speed sensor circuit DTC P0500 Vehicle Speed Sensor Malfunction; DTC P0503 Vehicle Speed Sensor "A" Intermittent / Erratic / High 
3. Stop light switch circuit DTC P0571 Brake Switch "A" Circuit 
4. CRUISE main indicator light circuit CRUISE MAIN INDICATOR LIGHT CIRCUIT 
5. Park / Neutral position switch circuit (for AA80E) MONITOR DESCRIPTION
5. Park / Neutral position switch circuit (for A760E) DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
5. Park / Neutral position switch circuit (for A760H) DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
6. ECM TERMINALS OF ECU 
Hunting (Speed is not constant.) 1. Vehicle speed sensor circuit DTC P0500 Vehicle Speed Sensor Malfunction; DTC P0503 Vehicle Speed Sensor "A" Intermittent / Erratic / High 
2. Malfunction in speed meter circuit SPEEDOMETER MALFUNCTION
3. Millimeter wave radar sensor power source circuit MILLIMETER WAVE RADAR SENSOR POWER SOURCE CIRCUIT 
4. Distance control ECU power source circuit DISTANCE CONTROL ECU POWER SOURCE CIRCUIT 
5. Distance control ECU TERMINALS OF ECU 
6. ECM TERMINALS OF ECU 
Vehicle speed setting cannot be canceled. (When Coast, Acceleration, Resume, Set speed change and Control switch are operated.) 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. ECM TERMINALS OF ECU 
Erroneous detection or lost sight of the vehicle ahead. 1. Clean laser sensor with soft cloth, etc. -
2. Improper aiming of sensor beam axis MILLIMETER WAVE RADAR SENSOR 
Alarm buzzer does not sound. 1. Buzzer circuit SKID CONTROL BUZZER CIRCUIT
2. VSC system HOW TO PROCEED WITH TROUBLESHOOTING
3. Millimeter wave radar sensor power source circuit MILLIMETER WAVE RADAR SENSOR POWER SOURCE CIRCUIT 
4. Distance control ECU power source circuit DISTANCE CONTROL ECU POWER SOURCE CIRCUIT 
5. Distance control ECU TERMINALS OF ECU 
6. ECM TERMINALS OF ECU 
Set distance cannot be changed. 1. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
2. Distance control switch DISTANCE CONTROL SWITCH CIRCUIT 
3. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
4. ECM TERMINALS OF ECU 
No display 1. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
2. ECM TERMINALS OF ECU 
No brake control (when decelerating) 1. VSC system HOW TO PROCEED WITH TROUBLESHOOTING
2. Distance control ECU power source circuit DISTANCE CONTROL ECU POWER SOURCE CIRCUIT 
3. Distance control ECU TERMINALS OF ECU 
4. ECM TERMINALS OF ECU 
Constant speed mode cannot be turned on. 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
3. ECM TERMINALS OF ECU 
Vehicle speed cannot be canceled with wiper HI. (Including automatic wiper) 1. Rain sensor system RAIN SENSOR CIRCUIT
2. Wiper switch circuit WIPER SWITCH (HI SPEED) CIRCUIT
3. Distance control ECU TERMINALS OF ECU 
4. ECM TERMINALS OF ECU 
Setting cannot be canceled in SNOW mode. 1. Pattern select switch circuit (for AA80E) DISASSEMBLY
1. Pattern select switch circuit (for A760E) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
1. Pattern select switch circuit (for A760H) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
2. Automatic transmission system (for AA80E) SYSTEM DESCRIPTION
2. Automatic transmission system (for A760E) SYSTEM DESCRIPTION
2. Automatic transmission system (for A760H) SYSTEM DESCRIPTION
3. ECM TERMINALS OF ECU 
Unable to adjust (complete) beam axis of millimeter wave radar sensor. 1. Check for DTC P1570 DTC P1570 RADAR SENSOR MALFUNCTION 
2. Check position, distance and angle of reflector MILLIMETER WAVE RADAR SENSOR 
3. Check installation of millimeter wave radar sensor -
4. Millimeter wave radar sensor MILLIMETER WAVE RADAR SENSOR 
5. Distance control ECU TERMINALS OF ECU 
6. ECM TERMINALS OF ECU 
Cannot change between constant speed control mode and vehicle-to-vehicle distance control mode 1. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
2. ECM TERMINALS OF ECU