When Carol Grubb bought her new car, the salesman told her that the "BA" on the invoice stood for "Brake Assist," but he wasn't able to tell her much more about what brake assist actually does and why she needs it. The Kissimmee resident didn't even ask about "BFD" — for "Brake Force Distribution." Newer vehicles are available with a growing number of safety features. But they can turn into a confusing shorthand. And while a window sticker might spell out what the initials stand for, they seldom explain what it really means. Let's do some decoding:
SRS: This is an easy one, but why the term "Supplemental Restraint System" is used may not be clear. SRS essentially refers to airbags, but the "supplemental" is used to indicate that airbags supplement seat belts — that they can't protect you unless you are buckled in.
Airbags are designed under the assumption that the driver and passengers will be held in the seat during an accident, and if they aren't, airbags can cause more harm than good. And speaking of airbags, they are multiplying, even in comparatively inexpensive cars.
ABS: "Anti-Lock Brakes" became popular more than 25 years ago and gradually migrated down to even the least-expensive vehicles. ABS uses an onboard computer to sense when each brake is about to lock, and it lets the wheel roll very slightly to prevent skidding.
One of the things about ABS is that it makes other technologies possible, such as:
ESC: "Electronic Stability Control" is marketed under different names by different manufacturers. But they typically perform the same function: When onboard sensors detect that the vehicle is sliding sideways, the onboard computer can actually cut the power, and apply the brakes to one, two, three or all four wheels (it's tied in with that ABS computer) until the vehicle is under control.
For example, if you drift off the side of the road into the dirt, then try to steer back onto the pavement, a vehicle without ESC can easily spin. For big, ungainly vehicles — full-sized SUVs, for instance — stability control is a gift. ESC, ABS and SRS — those are the Big Three.
BA and BFD: "Brake Assist" and "Brake Force Distribution" are similar — again, thanks to those onboard computers, the vehicle can sense when you are making a panic stop. Brake assist can actually increase braking pressure, and brake-force distribution can distribute that pressure between the four wheels for maximum efficiency.
TC: "Traction Control" may also be marketed under different acronyms for different manufacturers — but they typically work the same. When you give the vehicle gas and one or both drive wheels spin, traction control reduces the power until the wheel, or wheels, find enough traction to handle the amount of power you are giving the engine.
TPMS: "Tire Pressure Monitoring Systems" can tell you when there is a problem with one of the tires.