Circuit DescriptionThe engine oil temperature sensor is a variable resistor sensor and is used to measure the temperature of the engine oil in the oil rifle. The electronic control module (ECM) supplies 5 volts to the engine oil temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the engine oil temperature. When the oil temperature is low, the sensor or thermistor resistance is high. The ECM signal voltage only pulls down a small amount through the sensor to a ground. Therefore, the ECM senses a high signal voltage...

Circuit DescriptionDevices such as ABS controllers, autoshift transmissions, ASR systems, electronic displays, electronic information systems, electronic service tools, and vehicle electronic control unit(s) (VECUs) can communicate with the ECM over the SAE J1939 data link. Messages sent from the devices are received by the ECM and used for controlling the engine. The ECM also transmits information to these devices over the SAE J1939 data link. Component LocationThe SAE J1939 data link wiring and the SAE J1939 devices vary by OEM options. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position. Conditions for Setting...

Circuit DescriptionThe water-in-fuel sensor is attached to the fuel filter. The electronic control module (ECM) provides a 5 volt reference signal to the water-in-fuel sensor. When the water collected in the fuel filter covers the sensor probes, the water-in-fuel sensor then pulls the 5 volt reference voltage to ground, indicating high water accumulation in the fuel filter. Component LocationThe water-in-fuel sensor is integrated into the bottom of the OEM supplied suction fuel filter. The OEM supplied fuel filter is located on the intake side of the engine. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in...

Circuit DescriptionNormally, switches, accelerators, and other components are connected to the engine control module (ECM) directly through individual wires. Multiplexing allows those same components to be hard wired to an original equipment manufacturer (OEM) vehicle electronic control unit (VECU) or transmission electronic control unit (ECU) in the cab. Then component values and states from components such as sensors, accelerators, and switches can be transmitted from the OEM VECU to the Cummins® ECM over the SAE J1939 data link. Component LocationThe SAE J1939 data link wiring and the SAE J1939 devices vary by OEM options. Conditions for Running the DiagnosticsThe first...

Circuit DescriptionThe water-in-fuel sensor is attached to the fuel filter. The electronic control module (ECM) provides a 5 volt reference signal to the water-in-fuel sensor. When the water collected in the fuel filter covers the sensor probes, the water-in-fuel sensor then pulls the 5 volt reference voltage to ground, indicating high water accumulation in the fuel filter. Component LocationThe water-in-fuel sensor is integrated into the bottom of the OEM supplied suction fuel filter. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position. Conditions for Setting the Fault CodesThe ECM detects that the water-in-fuel...