Cumminz

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®...

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®...

Circuit DescriptionThe engine control module (ECM) monitors the NOx concentration in the engine’s exhaust gases using an aftertreatment intake NOx sensor and an aftertreatment outlet NOx sensor. By comparing these two values, the ECM is able to determine the conversion efficiency of the SCR catalyst and dosing system. Component LocationThe SCR catalyst is located in the vehicle’s exhaust system, after the diesel particulate filter and decomposition tube. Conditions for Running the DiagnosticsThis diagnostic has to meet specific engine and aftertreatment conditions to run and complete. Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the NOx conversion across...

Circuit DescriptionThe aftertreatment outlet NOx (nitrogen oxides) sensor is a smart device and communicates with the engine control module (ECM) via the J1939 data link. The aftertreatment outlet NOx sensor performs its own internal diagnostics and reports malfunctions back to the primary ECM using the J1939 data link. The NOx sensor is permanently attached to the NOx control module. They are serviced as a single component and can not be replaced individually. The aftertreatment outlet NOx sensor is used to measure the NOx emissions at the outlet of the aftertreatment system. Component LocationThe aftertreatment outlet NOx sensor location can vary...

Circuit DescriptionThe aftertreatment diesel exhaust fluid level sensor is used to monitor the diesel exhaust fluid level inside the diesel exhaust fluid tank. Component LocationThe aftertreatment diesel exhaust fluid tank level sensor is located in the aftertreatment diesel exhaust fluid tank. Location of the tank and level sensor is OEM dependent. Refer to the OEM service manual. Conditions for Running the DiagnosticsThe diagnostic runs continuously when the following conditions are met: Keyswitch is in the ON position or when the engine is running.Ambient temperature is above -20°C [-4°F].Vehicle altitude change is less than 305 m [1000 ft] in 1 hour.Conditions...