The 2021 Audi A4 is equipped with front pedestrian automatic emergency braking, front automatic emergency braking, pedestrian detection pre-collision warning system, audible warning pre-collision warning system, visual warning pre-collision warning system, dual front knee airbags, lane deviation sensors, rearview camera system, front side airbags, rear side curtain airbags, front side curtain airbags, regenerative braking system, 4-wheel abs, emergency braking preparation, anti-lockout power door locks, auto-locking power door locks, brake drying, hill descent off-road driving assist, auto off electronic parking brake, alarm anti-theft system, braking assist, hill holder control, disc rear brake, ventilated disc front brake, dual front airbags, vehicle immobilizer anti-theft system, power brakes, latch system child seat anchors, electronic brakeforce distribution, stability control, traction control, in dash rearview monitor, occupant sensing passenger airbag deactivation, front seatbelt pretensioners, front seatbelt force limiters, front emergency locking retractors, post-collision safety system impact sensor, rear seatbelt pretensioners, rear seatbelt force limiters, door unlock impact sensor, rear emergency locking retractors, front seatbelt warning sensor, fuel cut-off impact sensor.