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Problem Symptoms Table

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DYNAMIC LASER CRUISE CONTROL SYSTEM:

Symptom Suspected area Reference
Main switch cannot be turned on. (CRUISE main indicator light on combination meter does not illuminate.) 1. Cruise control switch circuit Refer to Cruise Control Switch Circuit
2. CRUISE main indicator light circuit Refer to Cruise Main Indicator Light Circuit
3. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
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 Refer to Cruise Control Switch Circuit
2. If the symptoms still occur after the above area has been inspected and has proven to be normal, replace the ECM. Refer to REMOVAL
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 Refer to Cruise Control Switch Circuit
2. Stop light switch circuit Refer to DTC P0571: Brake Switch "A" Circuit
3. Park/Neutral position switch circuit Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
4. Vehicle speed sensor circuit Refer to DTC P0500: Vehicle Speed Sensor Malfunction; DTC P0503: Vehicle Speed Sensor "A" Intermittent / Erratic / High
5. Pattern Select Switch Circuit (U151E) Refer to Pattern Select Switch Circuit
5. Pattern Select Switch Circuit (U151F) Refer to Pattern Select Switch Circuit
6. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
7. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
While vehicle is driven with cruise control, the control is canceled. (CRUISE main indicator light remains on.) 1. Cruise control switch circuit Refer to Cruise Control Switch Circuit
2. Vehicle speed sensor circuit Refer to DTC P0500: Vehicle Speed Sensor Malfunction; DTC P0503: Vehicle Speed Sensor "A" Intermittent / Erratic / High
3. Stop light switch circuit Refer to DTC P0571: Brake Switch "A" Circuit
4. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
5. Park/Neutral position switch circuit Refer to DTC P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
6. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Hunting (Speed is not constant.) 1. Vehicle speed sensor circuit Refer to DTC P0500: Vehicle Speed Sensor Malfunction; DTC P0503: Vehicle Speed Sensor "A" Intermittent / Erratic / High
2. If the symptoms still occur after the above area has been inspected and has proven to be normal, replace the ECM. Refer to REMOVAL
Vehicle speed setting cannot be canceled. (When coast, acceleration, resume, or set speed change function is operated with control switch.) 1. Cruise control switch circuit Refer to Cruise Control Switch Circuit
2. If the symptoms still occur after the above area has been inspected and has proven to be normal, replace the ECM. Refer to REMOVAL
Erroneous detection or lost sight of the vehicle ahead. 1. Clean laser sensor with soft cloth, etc. -
2. Improper aiming of sensor beam axis Refer to ADJUSTMENT
Alarm buzzer does not sound. 1. Buzzer circuit Refer to Skid Control Buzzer Circuit
2. VSC system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
3. Distance control ECU power source circuit Refer to Distance Control ECU Power Source Circuit
4. Distance control ECU Refer to REMOVAL
5. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Set distance cannot be changed. 1. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
2. Distance control switch circuit Refer to Cruise Control Switch Circuit
3. Distance control ECU Refer to REMOVAL
4. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
No information on the display 1. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
2. If the symptoms still occur after the above area has been inspected and has proven to be normal, replace the ECM. Refer to REMOVAL
No brake control (when decelerating) 1. VSC system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
2. Distance control ECU power source circuit Refer to Distance Control ECU Power Source Circuit
3. Distance control ECU Refer to REMOVAL
4. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Constant speed mode cannot be turned on. 1. Cruise control switch circuit Refer to Cruise Control Switch Circuit
2. Combination meter system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
3. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Vehicle speed cannot be canceled with wiper HI or LO. (Including automatic wiper) 1. Wiper motor circuit Refer to Front Wiper Motor Circuit
2. Wiper switch circuit Refer to Wiper and Washer Switch Circuit
3. Distance control ECU Refer to REMOVAL
4. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Setting cannot be canceled in SNOW mode. 1. Pattern select switch circuit (U151E) Refer to Pattern Select Switch Circuit
1. Pattern select switch circuit (U151F) Refer to Pattern Select Switch Circuit
2. Automatic transmission system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
3. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
Unable to adjust (complete) beam axis of laser sensor. 1. Check position, distance and angle of reflector Refer to ADJUSTMENT
2. Check installation of laser sensor Refer to INSTALLATION
3. Laser sensor Refer to REMOVAL
4. Distance control ECU Refer to REMOVAL
5. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM Refer to REMOVAL
Cannot change from constant speed control mode to vehicle-to-vehicle distance control mode. 1. Cruise control switch circuit Refer to Cruise Control Switch Circuit
2. Laser sensor power source circuit Refer to Laser Sensor Power Source Circuit
3. Distance control ECU Refer to REMOVAL
4. If the symptoms still occur after the above areas have been inspected and have proven to be normal, replace the ECM. Refer to REMOVAL
The CRUISE main indicator light remains blinking. 1. TC and CG terminal circuit Refer to TC and CG Terminal Circuit
2. If the symptoms still occur after the above area has been inspected and has proven to be normal, replace the ECM. Refer to REMOVAL