The IS’ optional pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The XF doesn’t offer pre-crash pretensioners.
For enhanced safety, the front seat shoulder belts of the Lexus IS are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The Jaguar XF doesn’t offer height-adjustable seat belts.
In the past twenty years hundreds of infants and young children have died after being left in vehicles, usually by accident. When turning the vehicle off, drivers of the IS are reminded to check the back seat if they opened the rear door before starting out. The XF doesn’t offer a back seat reminder.
The Lexus IS has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The XF doesn’t offer knee airbags.
The IS has a standard Secondary Collision Brake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The XF 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 IS offers optional Intuitive Parking Assist with Auto Braking that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The XF doesn’t offer automatic braking for stationary objects directly to the rear.
The IS offers an optional Panoramic View Monitor to allow the driver to see objects all around the vehicle on a screen. The XF only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
Both the IS and the XF have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front and rear seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning and available all wheel drive.