ADAS Features: AEB, ACC, LKA, and Related Systems
Know each feature's function, inputs, and limits. AEB (Automatic Emergency Braking) detects an imminent collision and applies brakes, often in stages (forward collision warning, then brake prefill, then full braking); it may be split into city (low speed) and interurban (higher speed) variants. ACC (Adaptive Cruise Control) maintains a set speed and a following gap using radar/camera; it may include stop-and-go. LKA (Lane Keeping Assist) applies steering torque to keep the vehicle centered; LDW only warns. Related systems include blind spot monitoring, rear cross-traffic alert, traffic sign recognition, and driver monitoring.
Traps abound: confusing LKA (intervenes) with LDW (warns); assuming AEB guarantees a stop (it mitigates, may not fully prevent); assuming ACC works in all conditions (often disabled in heavy rain or when sensors are blocked); confusing ACC with lane centering. Questions often test the difference between a system's designed operating envelope and real-world limits-AEB may not detect pedestrians at night, ACC may not see stopped vehicles.
Worked example: A customer says ACC "brakes late." Reason through: radar sees the lead vehicle, the gap setting and speed determine the following distance, and the brake controller actuates. If the complaint is about a stationary object, recall ACC may not respond to stopped vehicles-this is a design limit, not necessarily a fault. Always separate a feature limitation from a malfunction before diagnosing.