Generator Auto Start Belt Driven Alternator Monitoring
In your car, the D+/W.L. terminal is connected to the RED LAMP ALTERNATOR fitted in the dashboard. When you turn on the key, the lamp turns on as well. As a matter of fact the D+/W.L. terminal is about zero volt. A current flows into the alternator in order to 'excite' the winding. As soon as you crank the engine, a voltage gradually appears on the D+/W.L. terminal. When engine is running, the RED LAMP ALTERNATOR turns off. The Be1 does the same by using electronic circuits providing a proper automatic crank termination.