The X4 M’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Cayenne doesn’t offer pre-crash pretensioners.
The X4 M has standard Active Head Restraints, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the Active Head Restraints system moves the headrests forward to prevent neck and spine injuries. The Cayenne doesn’t offer a whiplash protection system.
Over 200 people are killed each year when backed over by motor vehicles. The X4 M offers optional Active Park Distance Control that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The Cayenne doesn’t offer backup collision prevention brakes.
The X4 M’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane. A lane departure warning system costs extra on the Cayenne.
The X4 M has a standard blind spot warning system which uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them and moves the vehicle back into its lane. A system to reveal vehicles in the Cayenne’s blind spot costs extra.
To help make backing out of a parking space safer, the X4 M 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 Cayenne.
The X4 M’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The Cayenne doesn’t offer a driver alert monitor.
Both the X4 M and the Cayenne have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, four-wheel antilock brakes, all wheel drive, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, rearview cameras and available around view monitors.