Sunday, July 21, 2024 Detailed Auto Topics
You May Also Like
AGCO Auto Quick Tip:

Try our new Category View for Detailed topics segregated by their topic.

Now it's even easier to find the information you need.

AGCO Auto Quick Tip:

You can also receive our Detailed Auto Topics, delivered to your computer, as soon as they are written, please subscribe to our RSS feed.

AGCO Automotive Detailed Topic Blog


Detailed Topics

Virtually all vehicles built today have anti-lock brakes. Many people still do not understand what they are or what they do.
Surprisingly ABS does not make the vehicle stop faster or better.

Anti-lock braking systems (ABS) were first installed on vehicles in the mid-eighties. Virtually all vehicles today are equipped with ABS. Even though the name states braking, ABS is actually NOT the brakes. Anti-lock braking is an electrical system that monitors wheel lockup. Just like most systems there is a dash light to indicate problems.

anti-lock braking system (ABS) warning light

When the vehicle is started the ABS light will remain on for a few seconds, while it executes several self-test. This is normal operation and light will quickly go out. If the light comes on while driving, the system has encountered a problem and is not working. This does NOT mean the brakes are going out. Fortunately, the hydraulic brakes will still work without ABS, much as vehicles did before ABS was added.

With ABS there are sensors that monitors the speed of the wheels. This is accomplished by a small toothed wheel that rotates with the wheel. As the teeth pass the sensor an electrical charge is produced. The faster the wheel rotates the higher the charge.

ABS sensor and tone wheel

A computer is used to monitor the wheels and constantly compare one to another. During braking, if one wheel slows or stops before the others it is assumed to be locked up. The computer then blocks the hydraulic pressure to that wheel and allows that brake to release. When the locked up wheel returns to the speed of the others the system releases and returns to monitoring.

This does not make the vehicle stop faster. By keeping the wheels from locking up, steering is maintained. For instance, if the wheels start to slide, traction is lost. When a sliding vehicle is steered, inertia can make it continue to travel straight. This can be detrimental in an evasive maneuver.

Skidding wheels may not respond to steering input

With anti-lock braking the wheels are kept from skidding. This helps maintain traction and greatly improves steering control. With good traction, the vehicle responds to the driver and a collision may be avoided.

Preventing skidding helps to maintain steering control

During ABS operation it is normal for the brake pedal to drop, lower than normal. The pedal may also vibrate and there may be noise. This is normal operation though it can be very surprising to an unprepared driver. Steady pressure on the brake pedal should be maintained until the vehicle stops.

The brake pedal may drop during ABS operation 

ABS brakes are pretty reliable and check themselves for problems. A problem is indicated when an ABS light comes on or if the system engages ABS when it should not. When this happens don’t panic, you will not lose your brakes. Instead call the folks at AGCO and have us diagnose the problem, as soon as possible.

Preventing ABS problems with maintenance or repairing the system, AGCO, it’s the place to go.

Post or Read Comments (0)

Please click the link above to leave your comments


Registered visitors are always invited to leave their comments and thoughts by using the form above. If you need to you can login here or register here.

You can also win a free AGCO coffee cup, by reporting any errors you find, with this form.