The S90’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The TLX doesn’t offer pre-crash pretensioners.
Both the S90 and TLX have child safety locks to prevent children from opening the rear doors. The S90 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The TLX’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The Volvo S90 offers optional built in child booster seats. They’re more crash worthy than an added child seat because of their direct attachment to the seat. Acura doesn’t offer the convenience and security of a built-in child booster seat in the TLX. Their owners must carry a heavy booster seat in and out of the vehicle; S90 owners can just fold their built-in child seat up or down.
The S90 has a standard Whiplash Protection System (WHIPS), which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the WHIPS moves the headrests forward to prevent neck and spine injuries. At the same time the pretensioning seatbelts fire, removing slack from the belts. The TLX doesn’t offer a whiplash protection system.
The S90 has standard Post-impact braking, which automatically apply the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The TLX 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 S90 has standard CTA Auto Brake that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The TLX doesn’t offer backup collision prevention brakes.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the S90. But it costs extra on the TLX.
The S90 has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. A system to reveal vehicles in the TLX’s blind spot costs extra.
To help make backing out of a parking space safer, the S90 has standard rear cross-path warning, helping the driver avoid collisions. Acura charges extra for Rear Cross Traffic Monitor on the TLX.
Both the S90 and the TLX have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, rearview cameras and driver alert monitors.