DTC C1702-55: Variant Coding Error: General Description

Smart Cruise Control (SCC) has additional function which helps to keep safety distance from the car ahead as compared with conventional cruise control. Control step is as follows.

1. SCC detects forward vehicle with radar sensor.
2. SCC calculates acceleration value according to distance and speed.
3. SCC transmits acceleration request to Hydraulic Electronic Control Unit (HECU) by CAN communication.
4. When deceleration is needed, HECU performs brake control. But when acceleration is needed, HECU calculates engine torque request and send it to Engine Management System (EMS) by CAN communication.
5. EMS performs acceleration control after receiving torque request.

   Forward Collision-Avoidance Assist (FCA) is designed to avoid collision or reduce damages from an accident caused by delayed braking or insufficient braking power due to distraction of the driver.

   System control process is as follows.

1. FCA uses a radar sensor and Lane Departure Warning System (LDWS)/Lane Keeping Assist System (LKAS) uses a camera sensor to detect vehicles ahead and data fusion. (L-CAN)
2. FCA identifies the FCA controllable vehicle using fusion detection data.
3. FCA calculates required deceleration speed depending on the speed/distance of vehicles ahead.
4. FCA transmits the calculated "required deceleration speed" to HECU. (CAN communication)
5. HECU calculates a required torque to implement "required deceleration speed" and then controls the brake control. (CAN communication)