Abstract: The invention relates to a charger for charging a battery and to a method for its operation. From the prior art, chargers with a charge-receiving mode for maintaining the battery voltage in a charged battery are known. The charge-receiving mode is characterized by two cyclically successive phases, a resting phase and a refreshing phase. During the resting phase, the battery discharges from an upper threshold voltage (UOG) to a lower threshold voltage (UUG). During the refreshing phase (A), the battery is charged again via a charge transformer (120) of the charger (100) from the lower to the upper threshold voltage. To minimize the power loss of the charger, it is proposed according to the invention that the charge transformer (120) in particular be switched off from the line voltage during the resting phase (R).

Abstract: A device for generating a trigger signal from ignition pulses of an ignition system, in which each one of the ignition pulses occurring in the ignition system is represented regardless of whether the ignition process is suppressed or not. The device can be connected to an ignition system which has at least one ignition coil with a primary winding and at least one secondary winding, where the first terminal of the primary winding is connected to the first terminal of a voltage source and the second terminal of the primary winding is connected by means of a controllable switch with a second terminal of the voltage source.

Abstract: A method is proposed for self-monitoring of microcomputer-controlled network devices (10) in motor vehicles which in accordance with applied transducer signals execute specified functions and upon detecting an error store a corresponding data word in memory. For indicating the error, the data word is converted into a signal train or voltage and detected by means of voltage measurement. This is preferably accomplished by inserting a diagnosis insert-plug (42) between the transducer lines and the network device (10). A voltmeter (47) can be connected to this test adapter and indicates this signal train or voltage. A specific type of error is associated with a specific voltage. As a result, a diagnosis which is as detailed as desired, of a complicated system, can be performed with a simple voltmeter (47) available in commerce.