Abstract: A method for checking functionality of a motor vehicle braking system. The braking system has a main module, including: hydraulically actuatable wheel brakes, pairs being assigned to respective brake circuits; at least one electrically actuatable wheel valve per wheel brake sets wheel-specific brake pressures; a pressure provision device actively builds up pressure in the wheel brakes; a pressure-medium reservoir at atmospheric pressure, and an auxiliary module, which has for each of two wheel brakes: a pressure sensor for measuring pressure in a wheel brake line; an open when deenergized isolating valve in the wheel brake line; a pump. At least one variable is measured to assess functionality of the braking system. Using least one acceptance criterion, and checked whether the variable satisfies the acceptance criterion. Determining at least one variable representing the viscosity of the brake fluid, and the at least one acceptance criterion depends on a variable representing viscosity.

Abstract: A method for checking functionality of a motor vehicle braking system. The braking system has a main module, including: hydraulically actuatable wheel brakes, pairs being assigned to respective brake circuits; at least one electrically actuatable wheel valve per wheel brake sets wheel-specific brake pressures; a pressure provision device actively builds up pressure in the wheel brakes; a pressure-medium reservoir at atmospheric pressure, and an auxiliary module, which has for each of two wheel brakes: a pressure sensor for measuring pressure in a wheel brake line; an open when deenergized isolating valve in the wheel brake line; a pump. At least one variable is measured to assess functionality of the braking system. Using least one acceptance criterion, and checked whether the variable satisfies the acceptance criterion. Determining at least one variable representing the viscosity of the brake fluid, and the at least one acceptance criterion depends on a variable representing viscosity.

Abstract: A invention relates to a device for detecting the position of a selector lever, in which the selector lever is connected to a switching device that transmits a signal to an evaluation device for a desired position of the selector lever. In a a device for detecting the position of a selector lever which operates reliably over its entire service life and can be produced at reasonable cost, the selector lever (1) is connected to a diaphragm (2, 3) arranged in the beam path between an optical transmitter (18) and an optical receiver (9, 10, 11, 12, 13, 14), the diaphragm (2, 3), which follows the movement of the selector lever (1), being designed in such a way as to be optically transparent in the desired position of the selector lever (1), as a result of which the optical receiver (9, 10, 11, 12, 13, 14) receives the signal from the optical transmitter (18) and transmits it to the evaluation device (15).