ELECTRONIC TECHNICIAN (ET) TROUBLESHOOTING - Continued
Speed Control Test.
System Operation Description:
The load sharing module (LSM) A4 provides a throttle signal to the ECM. The output for rated speed is a pulse
width modulated (PWM) signal at a constant frequency. The speed signal varies with the position of the
FREQUENCY adjust knob. The output signal is referred to as a duty cycle or as a PWM signal. The output signal is
expressed as a percentage between 0 and 100 percent for the speed adjust. Figure 9 shows the speed control