VSC helps prevent wheelslip and loss of traction by reducing engine power and applying brake force to the wheels that need it. (Figure 1)
Front wheelslip can occur when the front wheels lose traction during cornering and begin to drift toward the outside of the turn. (Figure 2) Rear wheelslip can occur when the rear wheels lose traction and cause the vehicle to slide around. (Figure 3)
Toyota?s VSC monitors your steering angle and the direction your vehicle is actually traveling and senses when your front or rear wheels begin to slip.
When it senses this loss of traction or slip, VSC reduces engine power and applies braking to the individual wheels that need it to help correct the slip and keep the vehicle in the intended path.
Traction Control (TRAC)
Traction Control helps maintain traction on wet, icy, loose or uneven surfaces by applying brake force to the spinning wheel(s).
Let?s say you?re driving and come upon a snowy or icy patch on an uneven road. (Figure 1)
If your vehicle gets stuck in the snow, wheelspin occurs, and you come to a stop. (Figure 2)
Toyota?s Traction Control sensors are activated when one of the wheels starts to slip. TRAC limits engine output and applies the brakes to the spinning wheel. (Figure 3) This transfers power to the wheels that still have traction to help you go safely on your way.
Anti-Lock Brake System (ABS)
ABS helps prevent brakes from locking up by "pulsing" brake pressure to each wheel to help you stay in control in emergency braking situations.
When something unexpected appears in your path, you instinctively swerve to avoid it and jam on the brakes. However, without ABS, the brakes can lock up, the vehicle starts to skid, and you struggle to stay in control. (Figure 1)
Toyota's ABS sensors detect which wheels are locking up and prevent the lockup by "pulsing" the brakes at each wheel independently. Pulsing releases brake pressure repeatedly for fractions of a second ? a reaction time not possible for humans. (Figure 2)
This means the wheels never stop rotating and that helps the car to avoid going into a skid, helping you stay in control. (Figure 3)
Electronic Brake-Force Distribution (EBD)
Toyota?s ABS technology has Electronic Brake-force Distribution (EBD) to help keep the vehicle more stable and balanced when braking.
If you have to stop abruptly, momentum causes the vehicle to tilt forward and reduces the brake force of the rear tires. (Figure 1)
But in a Toyota, EBD responds to sudden stops by redistributing brake force. Wheels with more braking effectiveness receive more brake force; wheels with less effectiveness receive less brake force. (Figure 2) This helps prevent brake lockup.
EBD is especially helpful when carrying cargo. Sensors recognize the extra load the cargo puts on the rear axle, so brake pressure on the rear wheels is increased because the extra weight improves braking effectiveness. (Figure 3)
Brake Assist (BA) 
Brake Assist is designed to detect sudden or ?panic? braking and adds the full pressure needed to help prevent a collision.
If something rolls out into the street in front of a vehicle, there?s only a split second to react. (Figure 1)
Because the reaction time is so short before the driver hits the brakes, not enough pressure may be applied. As a result, the car may not stop in time.
But in a Toyota, if a driver fails to apply enough pressure to the brake, the Brake Assist sensors will detect this sudden or ?panic? braking and add pressure. (Figure 2) This additional pressure can help the driver avoid hitting the object.
Smart Stop Technology 
As an added measure of safety, Toyota created the braking system enhancement known as Smart Stop Technology. This advanced technology automatically reduces engine power when both pedals are pressed at the same time under certain conditions.
Smart Stop Technology intervenes when the accelerator is depressed first (Figure 1) and the brakes are applied firmly for longer than one half second at speeds greater than five miles per hour (Figure 2).
In normal driving conditions, you won?t notice Smart Stop Technology as it is imperceptible. The feature doesn?t engage if the brake pedal is depressed before the accelerator pedal. This allows for vehicles starting on a steep hill to safely accelerate without rolling backward (known as hill start).
Toyota will install Smart Stop Technology in all new models by the end of 2010, making it one of the first full-line manufacturers to offer this braking technology as standard equipment.