A brake fluid pressure sensor senses the brake fluid pressure in a hydraulic braking system. The sensor is a type of pressure switch that shows and alerts a fault in the braking system. [1]
The fault could be lack of hydraulic fluid, low brake fluid in the reservoir, a broken hydraulic line or a bad master brake cylinder. The sensor is used to detect pressure differentials in the hydraulic system. If the car alerts a fault in the hydraulic system and the system checks out, the sensor itself may have failed. [2]
The sensor has an input port to measure the hydraulic braking pressure and an electrical connector output for a wire connection for feeding the warning light. Some brake failures do not trip the sensor into a fault mode.
A brake fluid pressure sensor is used in anti-lock braking system (ABS). ABS fault lights come on with unexpected wheel lock from the ABS system, but could also include low fluid in the reservoir. [3] [4] [5] [6]
New accident avoidance technologies system also use brake fluid pressure sensors. [7]
Many large heavy vehicles, like trucks, particularly those having multiple trailers use air brakes that use air pressure sensors.
An anti-lock braking system (ABS) is a safety anti-skid braking system used on aircraft and on land vehicles, such as cars, motorcycles, trucks, and buses. ABS operates by preventing the wheels from locking up during braking, thereby maintaining tractive contact with the road surface and allowing the driver to maintain more control over the vehicle.
Electronic stability control (ESC), also referred to as electronic stability program (ESP) or dynamic stability control (DSC), is a computerized technology that improves a vehicle's stability by detecting and reducing loss of traction (skidding). When ESC detects loss of steering control, it automatically applies the brakes to help steer the vehicle where the driver intends to go. Braking is automatically applied to wheels individually, such as the outer front wheel to counter oversteer, or the inner rear wheel to counter understeer. Some ESC systems also reduce engine power until control is regained. ESC does not improve a vehicle's cornering performance; instead, it helps reduce the chance of the driver losing control of the vehicle.
Hydropneumatic suspension is a type of motor vehicle suspension system, designed by Paul Magès, invented by Citroën, and fitted to Citroën cars, as well as being used under licence by other car manufacturers. Similar systems are also widely used on modern tanks and other large military vehicles. The suspension was referred to as Suspension oléopneumatique in early literature, pointing to oil and air as its main components.
Advanced driver-assistance systems (ADAS) are technologies that assist drivers with the safe operation of a vehicle. Through a human-machine interface, ADAS increase car and road safety. ADAS use automated technology, such as sensors and cameras, to detect nearby obstacles or driver errors, and respond accordingly. ADAS can enable various levels of autonomous driving.
Electronic brakeforce distribution or electronic brakeforce limitation (EBL) is an automobile brake technology that automatically varies the amount of force applied to each of a vehicle's wheels, based on road conditions, speed, loading, etc, thus providing intelligent control of both brake balance and overall brake force. Always coupled with anti-lock braking systems (ABS), EBD can apply more or less braking pressure to each wheel in order to maximize stopping power whilst maintaining vehicular control. Typically, the front end carries more weight and EBD distributes less braking pressure to the rear brakes so the rear brakes do not lock up and cause a skid. In some systems, EBD distributes more braking pressure at the rear brakes during initial brake application before the effects of weight transfer become apparent.
Brake fluid is a type of hydraulic fluid used in hydraulic brake and hydraulic clutch applications in automobiles, motorcycles, light trucks, and some bicycles. It is used to transfer force into pressure, and to amplify braking force. It works because liquids are not appreciably compressible.
Hydraulic machines use liquid fluid power to perform work. Heavy construction vehicles are a common example. In this type of machine, hydraulic fluid is pumped to various hydraulic motors and hydraulic cylinders throughout the machine and becomes pressurized according to the resistance present. The fluid is controlled directly or automatically by control valves and distributed through hoses, tubes, or pipes.
In automotive engineering, the master cylinder is a control device that converts force into hydraulic pressure. This device controls slave cylinders located at the other end of the hydraulic brake system and/or the hydraulic clutch system.
Power steering is a system for reducing a driver's effort to turn a steering wheel of a motor vehicle, by using a power source to assist steering.
A hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing glycol ethers or diethylene glycol, to transfer pressure from the controlling mechanism to the braking mechanism.
ATTESA is a four-wheel drive system used in some automobiles produced by the Japanese automaker Nissan, including some models under its luxury marque Infiniti.
A transmission control unit (TCU), also known as a transmission control module (TCM), or a gearbox control unit (GCU), is a type of automotive ECU that is used to control electronic automatic transmissions. Similar systems are used in conjunction with various semi-automatic transmissions, purely for clutch automation and actuation. A TCU in a modern automatic transmission generally uses sensors from the vehicle, as well as data provided by the engine control unit (ECU), to calculate how and when to change gears in the vehicle for optimum performance, fuel economy and shift quality.
An air brake or, more formally, a compressed-air-brake system, is a type of friction brake for vehicles in which compressed air pressing on a piston is used to both release the parking/emergency brakes in order to move the vehicle, and also to apply pressure to the brake pads or brake shoes to slow and stop the vehicle. Air brakes are used in large heavy vehicles, particularly those having multiple trailers which must be linked into the brake system, such as trucks, buses, trailers, and semi-trailers, in addition to their use in railroad trains. George Westinghouse first developed air brakes for use in railway service. He patented a safer air brake on March 5, 1872. Westinghouse made numerous alterations to improve his air pressured brake invention, which led to various forms of the automatic brake. In the early 20th century, after its advantages were proven in railway use, it was adopted by manufacturers of trucks and heavy road vehicles.
A pressure switch is a form of switch that operates an electrical contact when a certain set fluid pressure has been reached on its input. The switch may be designed to make contact either on pressure rise or on pressure fall. Pressure switches are widely used in industry to automatically supervise and control systems that use pressurized fluids.
The following outline is provided as an overview of and topical guide to automobiles:
Brake-by-wire technology in the automotive industry is the ability to control brakes through electronic means, without a mechanical connection that transfers force to the physical braking system from a driver input apparatus such as a pedal or lever.
S-AWC is the brand name of an advanced full-time four-wheel drive system developed by Mitsubishi Motors. The technology, specifically developed for the new 2007 Lancer Evolution, the 2010 Outlander, the 2014 Outlander, the Outlander PHEV and the Eclipse Cross have an advanced version of Mitsubishi's AWC system. Mitsubishi Motors first exhibited S-AWC integration control technology in the Concept-X model at the 39th Tokyo Motor Show in 2005. According to Mitsubishi, "the ultimate embodiment of the company's AWC philosophy is the S-AWC system, a 4WD-based integrated vehicle dynamics control system".
A collision avoidance system (CAS), also known as a pre-crash system, forward collision warning system (FCW), or collision mitigation system, is an advanced driver-assistance system designed to prevent or reduce the severity of a collision. In its basic form, a forward collision warning system monitors a vehicle's speed, the speed of the vehicle in front of it, and the distance between the vehicles, so that it can provide a warning to the driver if the vehicles get too close, potentially helping to avoid a crash. Various technologies and sensors that are used include radar (all-weather) and sometimes laser (LIDAR) and cameras to detect an imminent crash. GPS sensors can detect fixed dangers such as approaching stop signs through a location database. Pedestrian detection can also be a feature of these types of systems.
Sensotronic Brake Control (SBC) is an electro-hydraulic brake system developed by Daimler and Bosch. In this system, the wheel brake cylinders of a vehicle are operated through a servomechanism, offering precise and responsive braking.