The 2021 Hyundai Sonata's Highway Driving Assist (HDA) combines adaptive cruise control with lane centering for a comprehensive highway driving experience. When HDA isn't working, understanding its components and requirements helps identify the cause.
What Highway Driving Assist Does
HDA integrates multiple SmartSense features. It maintains set speed while adjusting for traffic (Smart Cruise Control), helps center the vehicle in lane (Lane Following Assist), and uses navigation data to adjust speed for curves and speed limit changes. This integration requires all components working together.
Why HDA May Not Work
HDA non-function can stem from any component issue. If Smart Cruise Control isn't working, HDA can't control speed. If Lane Following Assist is unavailable, HDA can't provide steering. Navigation system issues affect the advanced speed adjustment features. All systems must be operational for full HDA function.
Checking Individual Components
Test each HDA component separately to isolate the problem. Try using Smart Cruise Control alone—does it maintain speed and distance? Try Lane Following Assist alone—does it help center the vehicle? If individual features work but HDA doesn't, the integration may have issues.
System Requirements
HDA has specific operating requirements. Highway speeds are typically required. Navigation must be active with current map data. Camera and radar sensors must be unobstructed. The vehicle must be on a highway type road the system recognizes.