The Toyota Prius Prime has a standard driver’s side knee airbag mounted low on the dashboard. The knee airbag helps prevent the driver from sliding under the seatbelts or the main frontal airbag; this keeps the driver better positioned during a collision for maximum protection. A knee airbag also helps keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The ID.4 doesn’t offer knee airbags.
The Prius Prime has standard Active Headrests, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the Active Headrests system moves the headrests forward to prevent neck and spine injuries. The ID.4 doesn’t offer a whiplash protection system.
Both the Prius Prime and the ID.4 have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, rearview cameras, driver alert monitors, available blind spot warning systems, rear parking sensors and rear cross-path warning.
For its top level performance in IIHS driver-side small overlap frontal, moderate overlap frontal, side impact, rear impact and roof-crush tests, its standard front crash prevention system, its “Acceptable” rating in the new passenger-side small overlap crash test, and its headlight’s “Acceptable” rating, the Insurance Institute for Highway Safety grants the Prius Prime the rating of “Top Pick” for 2019, a rating granted to only 162 vehicles tested by the IIHS. The ID.4 has not been tested, yet.