Symptom Related Diagnostic Procedures

AUTOMATIC SPEED CONTROL DEVICE (ASCD)





Malfunction Detection Conditions

Fail Safe System Check





1. Turn ignition switch ON position.
2. Turn ASCD (Automatic Speed Control Device) main switch to ON and check if the "CRUISE indicator" blinks.
If the indicator lamp blinks, check the following.
^ ASCD steering switch. Refer to "DIAGNOSTIC PROCEDURE 5".





3. Drive the vehicle at more than 48 kph (30 MPH) and push SET/COAST switch.
If the indicator lamp blinks, check the following:
^ Vehicle speed sensor. Refer to "DIAGNOSTIC PROCEDURE 6".
^ ASCD pump circuit. Refer to "DIAGNOSTIC PROCEDURE 7".
^ Replace control unit.





4. Depress brake pedal slowly (brake pedal should be depressed more than 5 seconds)
If the indicator lamp blinks, check the following.
^ ASCD brake/stop lamp switch. Refer to "DIAGNOSTIC PROCEDURE 4".
5. END. (System is OK.)


TROUBLE DIAGNOSES





Symptom Chart





Diagnostic Procedure 1 (Power Supply And Ground Circuit Check)





Diagnostic Procedure 2 (ASCD Main Switch Check)





Diagnostic Procedure 3 (ASCD Hold Relay Check)





Diagnostic Procedure 4 (ASCD Brake/Stop Lamp Switch Check





Diagnostic Procedure 5 (ASCD Steering Switch Check)





Diagnostic Procedure 6 (Vehicle Speed Sensor Check)





Diagnostic Procedure 7 (ASCD Pump Circuit Check)





Diagnostic Procedure 8 (ASCD Actuator/Pump Check)

ELECTRICAL COMPONENTS INSPECTION





ASCD Main Switch

Check continuity between terminals by pushing switch to each position.





ASCD Brake Switch And Stop Lamp Switch

Check each switch after adjusting brake pedal.





Clutch Switch (For M/T Models)





Park/Neutral position Switch (For A/T Models)