Cumminz

Circuit DescriptionThe fuel shutoff valve is a device used by the electronic control module (ECM) to control the engine fuel supply. When the ECM energizes the engine fuel shutoff valve driver circuit, the engine fuel shutoff valve is opened. Zero voltage to the engine fuel shutoff valve will close the engine fuel shutoff valve. The engine fuel shutoff valve driver circuit utilizes a pulse width modulated (PWM) signal. A PWM signal is a pulsed voltage signal between 0-VDC and system voltage. Component LocationThe fuel shutoff valve is located near the fuel pump. Conditions for Running the DiagnosticsThis diagnostic runs continuously...

Circuit DescriptionThe fuel shutoff valve is a device used by the electronic control module (ECM) to control the engine fuel supply. When the ECM energizes the engine fuel shutoff valve driver circuit, the engine fuel shutoff valve is opened. Zero voltage to the engine fuel shutoff valve will close the engine fuel shutoff valve. The engine fuel shutoff valve driver circuit utilizes a pulse width modulated (PWM) signal. A PWM signal is a pulsed voltage signal between 0-VDC and system voltage. Component LocationThe fuel shutoff valve is located near the fuel pump. Conditions for Running the DiagnosticsThis diagnostic runs continuously...

Circuit DescriptionThe intake air heater improves starting and white smoke control in cold ambient conditions. The electronic control module (ECM) controls relays that switch power to the intake air heater. Air heaters on 12 volt systems will have two relays; 24 volt systems only require one relay. Component LocationThe intake air heater is located at the air inlet connection to the intake manifold. The location of the intake air heater relays will vary by vehicle and engine configuration. Conditions for Running the DiagnosticsThis diagnostic runs when the keyswitch is in the ON position and when the pulse width modulated (PWM)...

Circuit DescriptionThe intake air heater improves starting and white smoke control in cold ambient conditions. The engine control module (ECM) controls relays that switch power to the intake air heater. Air heaters on 12 volt systems will have two relays and 24 volt systems only require one relay. Component LocationThe intake air heater is located at the air inlet connection to the intake manifold. The location of the intake air heater relays will vary by vehicle and engine configuration. Conditions for Running the DiagnosticsThis diagnostic runs when the keyswitch is in the ON position and when the pulse width modulated...

Circuit DescriptionThe ambient air temperature sensor is a variable resistor sensor and is used to measure the temperature of the ambient air to determine if heating of the selective catalytic reduction (SCR) system is required. The electronic control module (ECM) supplies 5 volts to the ambient air temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the ambient air temperature. Component LocationThe location of the ambient air temperature sensor can vary, and is OEM dependent. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in...