The passenger compartment of the Mercedes-Benz CLA remained stable in the frontal offset test.  Protection was good for all critical body areas of both the driver and front passenger.  Mercedes-Benz showed that good protection would also be provided to the knees and femurs of occupants of different sizes and to those sitting in different positions.  Analysis of the deceleration of the impact trolley during the test, and analysis of the deformable barrier after the test, revealed that the Mercedes-Benz CLA would be a benign impact partner in a frontal collision.  In the full-width rigid barrier test, protection was good for all critical body regions of the driver and at least adequate for the rear seat passenger.  In the side barrier test, the Mercedes-Benz CLA provided good protection to all critical body areas and scored maximum points.  In the more severe side pole impact, protection of the chest was rated as marginal, based on dummy readings of rib compression, but was good for all other critical body areas.  Control of excursion (the extent to which a body is thrown to the other side of the vehicle when it is hit from the far side) was found to be adequate  The Mercedes-Benz CLA has a countermeasure to mitigate against occupant-to-occupant injuries in such impacts.  The airbag performed well in Euro NCAP’s tests with dummy readings indicating good protection for both the driver and passenger.  Tests on the front seats and head restraints demonstrated good protection against whiplash injuries in the event of a rear-end collision.  A geometric analysis of the rear seats also indicated good whiplash protection.  The car has an advanced eCall system which alerts the emergency services in the event of a crash, and a  system to prevent secondary impacts after the car has been in a collision.  Mercedes-Benz demonstrated that the doors would be openable to allow occupants to escape in the event of vehicle submergence.

In the frontal offset test, protection of all critical parts of the body was good for both the 6 and 10 year dummies.  In the side barrier test, protection of the 6 year dummy was good for all critical body areas and good or adequate for the 10 year dummy.  The Mercedes-Benz CLA senses when a child restraint has been put in the front passenger seat and automatically disables the airbag.  The system works robustly for various occupant and restraint system types, and was rewarded.  The Mercedes-Benz CLA is equipped with an indirect 'child presence detection' system, which issues a warning when it recognises that a child or infant may have been left in the car.  Indirect systems are no longer rewarded by Euro NCAP. All of the child restraint types for which the Mercedes-Benz CLA is designed could be properly installed and accommodated in the car.

The Mercedes-Benz CLA has an 'active' bonnet.  Sensors in the bumper detect when a pedestrian has been struck and actuators lift the bonnet surface to provide more space to the hard structures underneath.  Mercedes-Benz showed that the system worked robustly over a range of speeds and for different statures.  Accordingly, the car was tested with the bonnet in the raised, deployed position.  Protection of the head of a struck pedestrian or cyclist was predominantly good, with poor results recorded on the stiff windscreen pillars and at the base of the screen.  Protection of the pelvis was good at all test locations, as was that of the femur.  Protection of the knee and tibia was good or adequate at all test locations.  The autonomous emergency braking system of the Mercedes-Benz CLA responds to vulnerable road users such as pedestrians and cyclists, as well as to other vehicles.  In tests of its response to pedestrians, the system performed very well, including the protection of those to the rear of the car.  The system also performed well in tests of its reaction to cyclists including ‘dooring’, where a door is opened into the path of a cyclist approaching from behind.  The system’s response to motorcyclists was good.

Overall, the performance of the autonomous emergency braking (AEB) system was good in tests of its reaction to other vehicles.  A seatbelt reminder system is fitted as standard to the front and rear seats.  The car has a direct driver status monitoring system as standard, detecting driver fatigue and several types of distraction.  The lane support system gently corrects the vehicle’s path if it is drifting out of lane and also intervenes in some more critical situations.  The speed assistance system identifies the local speed limit.  The driver can choose to allow the limiter to be set automatically by the system.