Methods and apparatus to sense brake pad wear are disclosed. An example apparatus includes at least one memory device and at least one processor to execute instructions to, in response to an anti-lock braking system event, determine a volume of brake fluid in a brake piston chamber based on a flow rate of the brake fluid and a pressure within the brake piston chamber, and determine at least one of a thickness of a brake pad or a wear of the brake pad based on the volume of the brake fluid in the brake piston chamber and a volume of the brake piston chamber.

Methods and apparatus to sense brake pad wear are disclosed. An example apparatus includes at least one memory device and at least one processor to execute instructions to determine whether a braking event corresponds to an anti-lock braking event or a non-anti-lock braking event, in response to the braking event corresponding to the anti-lock braking event, determine at least one of a thickness of a brake pad or a wear of the brake pad based on at least operating parameters of a motor associated with pumping a brake fluid, and in response to the braking event corresponding to the non-anti-lock braking event, determine at least one of the thickness or the wear based on at least a first measurement from a rotary sensor operatively coupled to a brake rotor and a second measurement from a pressure sensor operatively coupled to a flow path of the brake fluid.

Methods and apparatus to sense brake pad wear are disclosed. An example apparatus includes at least one memory device and at least one processor to execute instructions to, in response to an anti-lock braking system event, determine a volume of brake fluid in a brake piston chamber based on a flow rate of the brake fluid and a pressure within the brake piston chamber, and determine at least one of a thickness of a brake pad or a wear of the brake pad based on the volume of the brake fluid in the brake piston chamber and a volume of the brake piston chamber.

A vehicle braking system includes brakes, a body, a braking linkage, a service brake comprising a braking piston movable relative to the body to act on the braking linkage and delimiting a service brake pressure chamber to place the braking piston in a service braking position. A parking brake acts on the braking piston and has a working configuration and a resting configuration. The parking brake includes a blocking device movable relative to the body to act on the braking piston and having a first position and a second position in which the blocking device is configured to immobilize the braking piston in a service braking position. A control device is movable relative to the body and has a locking position to hold the blocking device in the second position. A service brake indicator device receives information representing supply and/or venting of the service brake pressure chamber.

A method for functional testing of an electromechanical fill level monitoring device. In order to test the plausibility of a signal emitted by a fill level monitoring device of a first pressure medium chamber, a forced actuation of this fill level monitoring device is carried from time to time. This forced actuation is carried out in that a pressure medium delivery unit in a pressure medium circuit having the first pressure medium chamber is activated for a predefined period. This delivers the pressure medium fill level monitoring device into a second pressure medium chamber via a pressure medium connection. On the basis of the signal profile output by the fill level monitoring device, the proper operation of the fill level monitoring device is inferred in the electronic control unit.

A braking system having wheel brakes, a pressure supply device connected to the wheel brakes, a master brake cylinder actuated by a brake pedal and connected to the wheel brakes, and a brake fluid reservoir having a first and a second reservoir chamber separated by a partition wall, wherein the first reservoir chamber is connected to the pressure supply device, via which the pressure supply device is supplied with pressure medium, and the second reservoir chamber is connected to the master brake cylinder, via which the master brake cylinder is supplied with pressure medium The braking system is operated in a first operating mode when the first filling level is reached and a second operating mode when the second filling level is reached, and a hydraulic fallback level if a lowest filling level is reached.

To prevent the loss of any brake fluid from a hydraulic vehicle braking system after a detected leakage, a testing or a re-testing of a leak tightness of the vehicle braking system is carried out only after release, for example, after a repair of the vehicle braking system.

A method for functional testing of an electromechanical fill level monitoring device. In order to test the plausibility of a signal emitted by a fill level monitoring device of a first pressure medium chamber, a forced actuation of this fill level monitoring device is carried from time to time. This forced actuation is carried out in that a pressure medium delivery unit in a pressure medium circuit having the first pressure medium chamber is activated for a predefined period. This delivers the pressure medium fill level monitoring device into a second pressure medium chamber via a pressure medium connection. On the basis of the signal profile output by the fill level monitoring device, the proper operation of the fill level monitoring device is inferred in the electronic control unit.

The present disclosure relates to a method for testing a brake fluid sensor of a vehicle braking system, wherein the brake fluid sensor can indicate the fluid level in the fluid reservoir, wherein the method has the following steps: (1) Altering the fluid level in at least one region of the at least one fluid reservoir by means of at least one braking force generating device; and (2) Detecting whether the at least one brake fluid sensor emits a signal indicating the modified fluid level in the at least one region of the at least one fluid reservoir.

A testing method includes the steps of: (1) providing a negative pressure generator; (2) generating a negative pressure in a fluid passageway and a chamber which are in fluid communication with a guiding section of a fluid reservoir wherein a second sensing element is affixed to a guiding section of the fluid reservoir; (3) transferring a fluid flow stream from the guiding section to the chamber via the fluid passageway and drawing a float having a first sensing element from an upper position to a lower position within the guiding section; (4) generating a signal via the first and second sensing elements as the float moves relative to the second sensing element within the guiding section; and (5) transmitting a signal to at least one of a control unit or a graphical user display.