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Problem Symptoms Table

DYNAMIC LASER 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. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU 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 (DTC P0705) DTC P0705-757 Transmission Range Sensor Circuit; DTC P0705-758 Transmission Range Sensor Circuit; DTC P0851-775 Park / Neutral Switch Input Circuit Low
4. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
5. Hybrid vehicle control ECU 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 
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 (DTC P0705) DTC P0705-757 Transmission Range Sensor Circuit; DTC P0705-758 Transmission Range Sensor Circuit; DTC P0851-775 Park / Neutral Switch Input Circuit Low
6. Hybrid vehicle control ECU TERMINALS OF ECU 
Hunting (Speed is not constant.) 1. Vehicle speed sensor circuit DTC P0500 VEHICLE SPEED SENSOR MALFUNCTION 
2. Malfunction in speed meter circuit Speedometer Malfunction
3. Laser sensor power source circuit LASER 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. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU 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. Laser sensor power source circuit LASER 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. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU TERMINALS OF ECU 
No display 1. Combination meter system HOW TO PROCEED WITH TROUBLESHOOTING
2. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU TERMINALS OF ECU 
Vehicle speed cannot be canceled with wiper HI. (Including automatic wiper) 1. Rain sensor circuit Rain Sensor Circuit
2. Wiper switch circuit Wiper and Washer Switch Circuit
3. Distance control ECU TERMINALS OF ECU 
4. Hybrid vehicle control ECU TERMINALS OF ECU 
Setting cannot be canceled in SNOW mode. 1. Hybrid vehicle control ECU 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 laser sensor REMOVAL 
4. Laser sensor LASER SENSOR POWER SOURCE CIRCUIT 
5. Distance control ECU TERMINALS OF ECU 
6. Hybrid vehicle control ECU 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. Hybrid vehicle control ECU TERMINALS OF ECU