SCC(Smart Cruise Control) is a system added additional function that can keep distance from the car ahead safely according to speed of the car ahead by using radar sensor to existing conventional CC(Cruise Control) function. SCC system consists of radar sensor which measures distance and speed against control target (the car ahead), SCC ECU which calculates needed acceleration/deceleration value, ECM for torque control and ESC ECU for brake control and calculating needed torque.SCC calculates the time that vehicle reaches the control target by calculating relative speed and distance against control target based on radar sensor signal. In case of the time too short compared with setting value, SCC will decrease vehicle speed automatically.
SCC monitors vehicle speed signal from cluster with every reception of the CAN message. SCC sets this code when abnormal vehicle speed is received from cluster. System recovers to normal condition as soon as the signal is alright again.
Item
Detecting Condition
Possible cause
DTC Strategy
CAN message monitoring
Faulty cluster
Enable Conditions
Engine Run (engine rpm higher than 400 at least for 2s)
No low voltage/over voltage DTC
Threshold value
Abnormal vehicle speed is received from cluster.
Diagnosis Time
Continuous (minimum fault detect time : 500ms)
Recover Condition
As soon as the signal is alright again
Fail Safe
SCC Disengagement/Shutdown
Red SCC warning lamp turns on