Circuit DescriptionThe aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually. Component LocationThe aftertreatment SCR temperature sensor module is mounted on...

Circuit DescriptionThe ECM calculates a differential pressure across the turbocharger using the intake manifold pressure sensor and the crankcase pressure sensor. Component LocationThe intake manifold pressure sensor is located in the air intake horn. The crankcase pressure sensor is mounted to the crankcase breather filter housing. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the engine is running. Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the calculated differential pressure across the turbocharger was greater than a threshold. Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp immediately when the...

Circuit DescriptionThe crankcase breather heater is used to keep the crankcase breather filter housing from freezing. The ECM supplies battery voltage to the breather heater when heating is commanded. Component LocationThe crankcase breather heater is mounted to the crankcase breather filter housing. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running. Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the crankcase breather heater signal voltage was out of range high for more than 10 seconds. Action Taken When the Fault Code is ActiveThe ECM...

Circuit DescriptionThe crankcase breather heater is used to keep the crankcase breather filter housing from freezing. The ECM supplies battery voltage to the breather heater when heating is commanded. Component LocationThe crankcase breather heater is mounted to the crankcase breather filter housing. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running. Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the crankcase breather heater signal circuit was shorted to ground. Action Taken When the Fault Code is ActiveThe ECM logs the fault code immediately when...

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. Messages sent from OEM VECUs or transmission ECUs are received by the Cummins® ECM and used for controlling the engine. The Cummins®...