Cumminz

Circuit DescriptionNormally, switches, accelerators, and other components are connected to the engine ECM directly through individual wires. Multiplexing allows those same components to be hard wired to an 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® engine ECM over the SAE J1939 data link. Messages sent from OEM VECU’s or transmission ECU’s are received by the Cummins® engine ECM and used for controlling the engine. The Cummins® engine ECM and...

Circuit DescriptionNormally, switches, accelerators, and other components are connected to the 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 are used for controlling the engine. The Cummins® ECM and...

Circuit DescriptionThe injector solenoid valves control fueling quantity and injection timing. The electronic control module (ECM) energizes the solenoid by closing a high-side and a low-side switch. There are two high-side switches and six low-side switches inside the ECM. The injectors for cylinders 1 and 2 (front bank) share a single high-side switch that connects the injector circuit to the source of high voltage inside the ECM. Likewise, the injectors for cylinders 3 and 4 (rear bank) also share a single high-side switch. Each injector circuit has a dedicated low-side switch that completes the circuit path to ground inside the...

Circuit DescriptionThe selective catalytic reduction (SCR) outlet gas temperature sensor is used by the engine control module (ECM) to monitor the engine exhaust gas temperature exiting the catalyst. The ECM monitors the voltage on the SIGNAL pin and converts this to a temperature value. Component LocationThe SCR outlet exhaust gas temperature sensor is located in the exhaust aftertreatment system. It is located at the outlet of the SCR catalyst. 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 temperature at the SCR catalyst...

Circuit DescriptionThe aftertreatment diesel exhaust fluid line heater 1 is controlled by the aftertreatment diesel exhaust fluid controller, and receives power through the switch side of the diesel exhaust fluid line heater relay. Component LocationThe aftertreatment diesel exhaust fluid line heater 1 is located on the supply line, between the diesel exhaust fluid dosing unit and diesel exhaust fluid dosing valve. Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position and the heater is commanded ON. Conditions for Setting the Fault CodesThe aftereatment diesel exhaust fluid controller detects that the line heater voltage...