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Problem Symptoms Table

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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 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 INSPECTION PROCEDURE
4. Transmission control switch circuit (3UZ-FE) MONITOR DESCRIPTION
4. Transmission control switch circuit (2GR-FSE 2WD) TRANSMISSION CONTROL SWITCH CIRCUIT
4. Transmission control switch circuit (2GR-FSE 4WD) DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"
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 INSPECTION PROCEDURE
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 REMOVAL 
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 (3UZ-FE) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
1. Pattern select switch circuit (2GR-FSE 2WD) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
1. Pattern select switch circuit (2GR-FSE 4WD) PATTERN SELECT SWITCH SNOW MODE CIRCUIT
2. Automatic transmission system (3UZ-FE) SYSTEM DESCRIPTION
2. Automatic transmission system (2GR-FSE 2WD) SYSTEM DESCRIPTION
2. Automatic transmission system (2GR-FSE 4WD) 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 REMOVAL 
3. Check installation of millimeter wave radar sensor -
4. Millimeter wave radar sensor REMOVAL 
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