METHOD AND CIRCUIT FOR DETECTING A FAILURE IN AN INDICATOR LIGHT

摘要

The invention relates to a method for detecting a failure in an auxiliary indicator light, for instance on a trailer, which is connected to a main indicator light installation, for instance of a tractive vehicle, which main indicator light installation comprises an indicator pulse generator, a number of main indicator lights actuated thereby and a malfunction detection circuit monitoring the status of the main indicator lights, wherein an error signal is generated to the malfunction detection circuit of the main indicator light installation when an error condition is determined in the auxiliary indicator light, and wherein the operation of the indicator pulse generator is monitored and the error signal is provided as long as the indicator pulse generator is in operation. By thus providing the error signal during both the "on" and "off" phase of the indicator lights an error condition of the auxiliary indicator light is detected under all conditions by the malfunction detection circuit, irrespective of the moment of checking. The invention further relates to a circuit for performing this method.