Car Buying Glossary

Anti-lock Brake Systems (ABS) work to prevent a vehicle’s brakes from locking up during hard braking. This helps maximize braking efficiency and effectiveness. Magnetic wheel-speed sensors are used to detect sudden braking. The system responds by temporarily releasing brake pressure and then reapplying optimal pressure to the brakes. This process is repeated rapidly, multiple times per second, to help achieve safe braking while helping the driver maintain steering and vehicle control.

Brake assist2 is designed to enhance braking effectiveness in emergency situations. Research indicates that slightly fewer than half of drivers fail to apply the brakes quickly enough, or with sufficient force, to adequately avoid obstacles when “panic braking”. The Brake Assist system automatically engages when it detects such an inadequate braking attempt, providing additional force to the brakes. The system is capable of significantly reducing the distance traveled before stopping.

Electronic Brake-force Distribution (EBD) is a system that works with a vehicle’s Anti-lock Brake System (ABS) to optimize the functionality and effectiveness of the vehicle’s brakes. The system uses feedback from sensors on all four wheels to determine variables such as road conditions, vehicle speed, weight distribution, etc. It increases or decreases brake pressure as needed to maximize vehicle stability and stopping efficiency

Electronic Power Steering (EPS) is a modern innovation that provides finely-tuned, precision steering control, improved handling, and greater fuel efficiency, compared to older hydraulic systems, which are somewhat less responsive and more taxing on the vehicle’s engine. The system depends on software and input from various sensors, including torque sensors in the steering shaft, and safety systems such as stability and traction control systems.

Toyota’s proprietary VSC1 is a form of Electronic Vehicle Stability Control; computerized technology that serves to enhance the vehicle’s control while driving, by enhancing traction. Traction refers to the ability of a vehicle’s tires to grip the road. In technical terms, this is called “adhesive friction”. Traction enhancement is accomplished by sensing a loss of traction, which could result in skidding, and automatically applying the appropriate brake or brakes to help prevent loss of steering control.

A feature that takes the stress out of starting a vehicle parked or stopped on an uphill incline. Without Hill Start Assist Control (HAC)4, drivers might find it challenging to switch from the brake to the accelerator quickly enough to avoid rolling backwards. HAC prevents this uncontrolled downhill travel by keeping the brake engaged a moment (about two seconds) after you release it, when parked facing uphill. The brief delay in disengaging the brake gives the driver adequate time to accelerate and take control of the vehicle’s motion. The feature should not be used as a substitute for engaging the parking brake when parking.

A unit of measurement that describes the power of an engine; it is equivalent to 550 foot-pounds per second. One horsepower is needed to move 33,000 pounds one foot in one minute, for example. Power is the rate at which work is accomplished. By definition, moving a vehicle from point A to point B involves work.

Many modern automobile manufacturers now make use of LED lighting technology to enhance styling, add design flexibility, and save energy. Light-emitting diode (LED) lighting is based on semi-conductor technology. LEDs produce virtually no heat and consume far less energy than older incandescent lights, while lasting much longer. In contrast to the incandescent bulbs used in older vehicles, which occasionally require replacement, today’s LEDs are expected to outlast the vehicles they help illuminate.

Toyota’s Smart Stop Technology (SST)3 is designed to reduce engine power when the brake is firmly applied helping to bring the vehicle to a stop, even if the accelerator pedal is firmly depressed.

The Tire Pressure Monitoring System (TPMS)5 is a safety feature that monitors the pressure in your tires and notifies you when one or more tires become critically under-inflated. A low-tire-pressure icon (in conjunction with a “!” symbol) lights up on the dashboard display when the system detects a significant deficit in the pressure of one or more tires. The system represents a significant contribution to driver confidence, as adequate tire pressure plays an important role in a vehicle’s ability to grip the road and come to a stop within a reasonable distance. A warning from the TPMS should always be addressed immediately.

Also called moment of force, or simply moment, torque refers to the tendency of a force to rotate an object around an axis. Mathematically, torque refers to the rate of change of angular momentum of an object. In the automotive industry, it refers specifically to the measured ability of a gear or shaft to rotate, overcoming turning resistance.

Traction Control (TRC) is a system to help monitor—and maintain—traction between the tires and the road. Engineers refer to this gripping ability as “adhesive friction”. When accelerating or starting under slippery conditions, such as when the road surface is wet, TRC engages to improve the ability of a vehicle’s wheels to grip the road surface. If inappropriate wheel spin is detected, the system reduces power to the wheel or wheels affected, or applies the brakes as needed to improve traction and prevent vehicle instability.