For enhanced safety, the front and rear seat shoulder belts of the Volkswagen ID.4 have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Hyundai Ioniq Electric doesn’t offer pretensioners for the rear seat belts.
The ID.4’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Ioniq Electric doesn’t offer pre-crash pretensioners.
Both the ID.4 and Ioniq Electric have child safety locks to prevent children from opening the rear doors. The ID.4 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The Ioniq Electric’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The ID.4 has a standard Automatic Post-Collision Braking System, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Ioniq Electric doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
Over 200 people are killed each year when backed over by motor vehicles. The ID.4 has standard Maneuver Braking that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The Ioniq Electric doesn’t offer backup collision prevention brakes.
The ID.4 has all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Ioniq Electric doesn’t offer all-wheel drive.
To help make backing out of a parking space safer, the ID.4 has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Rear cross-path warning costs extra on the Ioniq Electric.
Both the ID.4 and the Ioniq Electric have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, 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 and driver alert monitors.
The Volkswagen ID.4 weighs 1197 to 1556 pounds more than the Hyundai Ioniq Electric. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.
For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its standard headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the ID.4 its highest rating: “Top Safety Pick Plus” for 2021, a rating granted to only 76 vehicles tested by the IIHS. The Ioniq Electric has not been tested, yet.