Abstract: The invention relates to an arrangement which permits operating characteristic variables such as the crankshaft rotational speed and the content of exhaust gas components to be determined in the workshop. The sensor is mounted so as to be stationary in the exhaust gas system or is only intermittently mounted in this system. According to one arrangement of the invention, the exhaust gas sensor includes a first device which receives the pressure of the exhaust gas of the engine. In this way, the crankshaft rotational speed can be arrived at. A second device is arranged in the exhaust gas sensor which has an output signal which is a measure for the content of an exhaust gas component. A further embodiment of the arrangement of the invention includes an exhaust gas sensor having a first device which is configured as a fault meter, temperature sensor or as a hot wire flow meter. Other devices can be utilized to detect further variables of the exhaust gas and evaluate the same.

Abstract: A method and device for testing inductive pulse generators of the type used as wheel-rpm feedback transducers in anti-wheel-lock action in automotive braking systems. Within a portion of the range of frequencies at which such inductive pulse generator produces output voltage pulses, the amplitude and frequency of such pulses vary approximately in proportion to each other. In accordance with the present invention, a quality characterization signal is derived which varies similarly to the ratio of pulse amplitude and pulse frequency. Thus, within such frequency range, or equivalently within the corresponding range of wheel rotation speed in the context specified above, the value of the quality characterization signal will be independent of the frequency or wheel rpm at which the test happens to be performed.

Abstract: A method of testing the operativeness of a vehicular anti-wheel-lock system of the type whose control device includes a self-monitoring circuit which, when the control device is switched on, initiates a test program and upon detection of system malfunction generates a malfunction signal and also switches off the control device. To test the self-monitoring circuit, the test program is repeatedly initiated by application of artificially generated wheel-rotational-speed signals and operating voltage is applied to the control device with each initiation of the test program. Predetermined faults are simulated, e.g., by the interruption of control lines of the control device, so that upon each implementation of the test program the production of a malfunction signal or the absence of one indicate whether the self-monitoring circuit is operating properly with respect to the fault being simulated.

Abstract: A method and an apparatus for the determination of the injection time in externally ignited internal combustion engines, which serve to provide the optimal injection time under given operating conditions, this injection time being derived on the basis of the rpm and the angle of the throttle valve wherein a basic injection time signal is derived from an rpm and a throttle valve angle signal and this signal is subsequently modified by means of a controlled nonlinear function generator to closely approximate an empirically ascertained optimal value for the injection time under given operating conditions, the basic injection time signal being formed in a divider circuit to provide an output signal which is fed to at least one nonlinearity function generator controllable in accordance with the throttle valve angle and the rpm.