Evolution of ABS
Since nearly 100 years ago, anti-lock brake technology has been in use. Anti-skid brake systems have been used on aircraft since World War II. The earliest antilock braking systems for automobiles date back to the 1920s. As a positive step towards improved safety and vehicle control in slippery conditions, anti-skid and anti-lock brakes became more common on cars and trucks in the 1990s.
ABS may seem complicated but it is actually very simple in its function. ABS controls module detects a slowdown in wheel rotation and modulates brake application to steer you out of trouble. A conventional skid causes steering control to be lost, and the vehicle will continue moving in the same direction as the skid. Anti-lock brake pulses the brakes to give the skid more control.
An ABS typically consists of four wheels sensors, sometimes two or three, an anti-lock electronic controller module and a hydraulic control device. This system applies hydraulic pressure to all four brakes under normal conditions and pulses each brake when there is a skid.
ABS function
The first anti-lock brake systems were not electrical, but hydromechanical. They could be mechanically controlled to control brake application. Contemporary anti-lock braking systems are computer- controlled, electrohydromechanical brake hydraulic systems. Either the ABS electronic controller or module can be integrated with the hydromechanical brake controller, or it can be independent. You can also have electrical relays that activate when the system is in use.
ABS Types
There are three basic types of anti-lock braking systems: four-channel/four-sensor, three-channel/three-sensor and one-channel/one-sensor. The four-channel system is the best choice as it can micromanage the brake action of a skid by only pulsing the affected wheel. Three-channel systems have one ABS sensor in the rear and two sensors in the front. The rear ABS sensor can be found in the axle housing. It affects both rear brakes. One-channel systems are rear anti-lock brakes that only have one ABS sensor located in the rear axle housing. One-channel systems are most common for trucks equipped with rear antilock brakes.
Anti-lock brakes should not be used to abruptly stop. Instead, use a steady, solid pedal to allow the anti-lock brake system to do its job.
ABS problems
The ABS control module in a vehicle is designed to alert the driver with a warning lamp if the system is malfunctioning. A malfunction in the ABS module is rare. It’s usually one or more sensors or the wiring that connects to them. Most ABS problems are caused by sensors that become contaminated with metal shavings or debris.
Sensor wiring can also be damaged and cause malfunctions, which may result in no or intermittent continuity. Brake fluid can get contaminated in more corrosive environments, or from serious neglect of the brake system. The hydraulic control unit may fail to function.
You should first check the ABS wiring and brake sensors for any malfunctions. Check the brake sensors for metal shavings or other debris. This could lead to false feedback to your ABS controller. False feedback can cause the ABS to not work as it should or trigger it when it shouldn’t.
Although you may not have an ABS scanner tool at your home, Central Texas Auto Care we have a brand new scan tool it’s useful if there is no physical cause for your ABS problems. we can begin your ABS troubleshooting once the scan tool has produced a fault code. No matter what the problem is, it is much easier to repair once the fault has been established.
