Electronic Stability Control
Electronic Stability Control is often called the greatest automotive safety feature developed since the seatbelt. Regardless, most drivers don’t know what ESC does, or whether or not it’s installed in their vehicle. If your vehicle is a 2013 model or later, you definitely have ESC: Transport Canada’s Motor Vehicle Safety Standard 126 required that all vehicles manufactured after September, 2011 be equipped with ESC. If your car is older, you’ll need to consult your owner’s manual.
What is ESC?
ESC is an extension of your Anti-Lock Braking System (ABS). ABS replaced the need to pump the brakes when experiencing a loss of traction. It monitors the rotational speed of each wheel. If one wheel is rotating significantly slower than the others (indicating it has insufficient traction), it decreases the brake pressure. Once the wheel is rotating more at an appropriate speed, the brake pressure is increased again to help slow the vehicle. These adjustments can happen upwards of ten times per second.
Like ABS, ESC features traction sensors in every wheel and adjusts braking power to individual wheels. But Electronic Stability Control SC adds a yaw sensor, accelerometer, and steering angle sensor. With all that equipment, ESC applies braking pressure only the wheels that will help you return to the direction your wheel is pointing. Some ESC systems can even reduce the engine’s power to mitigate the loss of traction.
While Electronic Stability Control may become active in a variety of driving scenarios, it is most useful during sudden swerves. For example, if you need to make a quick lane change to avoid a deer, ESC would help you exit your lane. Also, crucially, it helps you center your vehicle after doing so. Additionally, some situations demand that you turn ESC off.
If your vehicle is stuck, disable the ESC. If you’re trying to pull your vehicle out of deep snow, you don’t want Stability Control applying the brakes. Of course, you don’t want your wheels to spin out. So, put your vehicle into first gear and apply the accelerator gently.
You should also disable ESC if you’re driving off-road or with a mini, spare tire.
By the Numbers
Okay, that sounds great. But you might be wondering how effective ESC is at actually mitigating the risk of collisions in adverse driving conditions, or during aggressive maneuvers. Well, all research on the topic indicates that ESC dramatically reduces the risk of (mostly) single-vehicle collisions.
Transport Canada’s recently demonstrated that ESC could reduce loss of control among light-duty vehicles by 29%. They go on to estimate that those numbers would correlate to roughly 225 fewer deaths and 755 fewer serious injuries per year. Meanwhile, in the United States, the Insurance Institute for Highway Safety found that ESC would reduce collisions involving a single vehicle by 41% – which is either an indictment of statistical analysis or American drivers.
As with all driver safety features, ESC can’t replace responsible, attentive driving. But it does add a little peace of mind.