Alternator Load Signal

Alternator - load signal

Function
This sensor a special output of the alternator that determines the level of electrical load. The alternator must generate more current when electrical loads such as headlights, rear-window defroster are activated. In doing so, the alternator creates a greater load on the engine. The signal from the alternator is pulse width modulated (PWM). The duty cycle is variable between 0% and 100% and is proportional to the alternator load. However, the signal is too low to compensate for the disturbances that occur at idle speed. The signal enables adjustment of the idle speed.

Installation Location
The alternator is installed on the front side of the engine.

Failure
If the PWM signal fails while the vehicle is driving at low speed, idle speed monitoring of the engine will be impaired when additional electrical loads are switched on.