Rear crash prevention

IIHS rates vehicles for rear crash prevention, a group of technologies that help drivers avoid colliding with other vehicles or fixed objects when traveling in reverse. The technologies include parking sensors, rear automatic braking and rear cross-traffic alert.

The ratings are based on the presence of parking sensors and rear cross-traffic alert and, for autobrake, the system’s performance in a series of track tests at 4 mph. Vehicles with rear crash prevention technologies can be rated basic, advanced or superior.

Rated vehicles

Test scenarios

The rear autobrake tests are based on a protocol developed by RCAR, an international consortium of insurance-funded research organizations working to reduce the injuries and property damage associated with automobile crashes.

Reversing car-to-car, 16" overlap:
This scenario simulates backing out of a parking space toward a stationary vehicle (shown in gray). Test runs include reversing straight back and from the left and right toward the target. If autobrake fails to prevent a collision, the test vehicle will strike the corresponding portion of the target vehicle bumper with an overlap of 16 inches.

Reversing car-to-car, 45° angle:
This scenario involves reversing out of a parking space toward a stationary vehicle (shown in gray). Test runs include reversing straight back and from the left and right toward the target. If autobrake fails to intervene, the corner of the test vehicle's bumper will strike the center of the target vehicle bumper.

Reversing car-to-car, 10° angle:
This scenario simulates backing toward the side of an adjacent stationary vehicle (shown in gray). The test involves reversing straight back toward the target vehicle parked at a 10° angle to the test vehicle.

Reversing toward fixed pole:
This scenario simulates backing into a pole or garage pillar. The test car reverses straight toward a bollard that is aligned midway between the center line and bumper corner.

How points are assigned

In the ratings, autobrake carries the most weight because research shows it provides the biggest crash reductions. For autobrake, systems are assigned points from the track tests based on the number of runs that either avoid or barely hit the target, reducing speeds to less than 1 mph.

• Front crash prevention - basic
  Basic
  0.5 to 1.4 points
• Front crash prevention - advanced
  Advanced
  1.5 to 4.4 points
• Front crash prevention - superior
  Superior
  4.5 to 6 points

Test protocol

Rear crash prevention test protocol Version I, July 2024