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Problem Symptoms Table

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Dynamic Radar Cruise Control System 

PROBLEM SYMPTOMS 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 on 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 DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
4. Shift paddle switch circuit SHIFT PADDLE SWITCH CIRCUIT
5. Vehicle speed sensor circuit DTC P0500 VEHICLE SPEED SENSOR MALFUNCTION; DTC P0503 VEHICLE SPEED SENSOR "A" INTERMITTENT / ERRATIC / HIGH 
6. Transmission control switch circuit (760E) TRANSMISSION CONTROL SWITCH CIRCUIT
6. Transmission control switch circuit (960E) TRANSMISSION CONTROL SWITCH CIRCUIT
6. Transmission control switch circuit (760H) TRANSMISSION CONTROL SWITCH CIRCUIT
7. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
8. ECM TERMINALS OF ECU 
While vehicle is driven with cruise control, the control is canceled. (CRUISE main indicator light remains on.) 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. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
5. Park/Neutral position switch circuit DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT)
5. Shift paddle switch circuit SHIFT PADDLE SWITCH CIRCUIT
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 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 
Vehicle speed setting cannot be canceled. (When coast, acceleration, resume, set speed change function is operated with control switch.) 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 radar 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 circuit DISTANCE CONTROL SWITCH CIRCUIT 
3. Cruise control switch circuit CRUISE CONTROL SWITCH CIRCUIT 
4. Distance control ECU TERMINALS OF ECU 
5. ECM TERMINALS OF ECU 
No information on the 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 (760E) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
1. Pattern select switch circuit (960E) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
1. Pattern select switch circuit (760H) PATTERN SELECT SWITCH SHOW MODE CIRCUIT
2. Automatic transmission system (760E) HOW TO PROCEED WITH TROUBLESHOOTING
2. Automatic transmission system (960E) HOW TO PROCEED WITH TROUBLESHOOTING
2. Automatic transmission system (760H) HOW TO PROCEED WITH TROUBLESHOOTING
3. ECM TERMINALS OF ECU 
Unable to adjust (complete) beam axis of millimeter wave radar sensor. 1. Check for DTC P1570 DTC CHECK/CLEAR 
2. Check position, distance and angle of reflector MILLIMETER WAVE RADAR SENSOR 
3. Check installation of millimeter wave radar sensor MILLIMETER WAVE RADAR SENSOR 
4. Millimeter wave radar sensor TERMINALS OF ECU 
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. Millimeter wave radar sensor power source circuit MILLIMETER WAVE RADAR SENSOR POWER SOURCE CIRCUIT 
3. Distance control ECU TERMINALS OF ECU 
4. ECM TERMINALS OF ECU