The passenger compartment remained stable in the frontal impact. Dummy readings showed good protection of the knees and femurs of both the driver and passenger. Suzuki showed that a similar level of protection would be provided to occupants of different sizes and to those sat in different positions. In the side impact barrier test, the SX4 scored maximum points, with good protection of all body areas. In the more severe side pole impact, protection of the chest and abdomen was adequate and that of the head and pelvis was good. The seat and head restraint provided good protection against whiplash injury in the event of a rear-end collision.
Based on dummy readings in the dynamic tests, the SX4 scored maximum points for its protection of the 1½ year infant. In the frontal impact, forward movement of the 3 year dummy, sat in a forward-facing restraint, was not excessive. In the side impact, both dummies were properly contained within the protective shells of their restraints, minimising the likelihood of dangerous head contact with parts of the car interior. The passenger airbag can be disabled to allow a rearward-facing child restraint to be used in that seating position. Clear information is provided to the driver and the dangers of using a rearward facing child seat without first disabling the airbag are clearly and permanently shown inside the car. The system met Euro NCAP's requirements and was rewarded. The user manual does not state that the front passenger seat needs to be set to its highest position for the group 1 Universal restraint to be properly accommodated and, for that reason, the installation check for that restraint was failed for that seating position. The group 2/3 restraint was unstable in the rear centre seating position. Otherwise, all restraints for which the car is designed could be properly installed and accommodated by the car.
The bumper scored maximum points for its protection of pedestrians' legs, with good results in all areas tested. However, the front edge of the bumper scored no points, with poor protection of the pelvis area. The bonnet surface provided mostly good or adequate protection to the head of a struck pedestrian with poor results being recorded only at the stiff windscreen pillars.
Electronic stability control is standard equipment and met Euro NCAP's test requirements. A standard-fit seatbelt reminder covers the front and rear seats. A driver-set speed limitation device is standard equipment and passed Euro NCAP's test requirements for systems of that type.