Paccar

Reason:Engine Coolant Temperature – Data Valid But Below Normal Operational Range – Moderately Severe Level. Engine coolant temperature is below normal operating temperature limits. Effect:None on performance Circuit Description:The coolant temperature sensor is a variable resistor sensor and is used to measure the temperature of the coolant of the engine. The engine control module (ECM) supplies 5 volts to the coolant temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the coolant temperature. Component Location:The engine coolant temperature sensor is located on the thermostat housing. Conditions for Running...

Reason:Engine Coolant Temperature – Data Valid But Below Normal Operational Range – Moderately Severe Level. Engine coolant temperature is below normal operating temperature limits. Effect:None on performance Circuit Description:The coolant temperature sensor is a variable resistor sensor and is used to measure the temperature of the coolant of the engine. The engine control module (ECM) supplies 5 volts to the coolant temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the coolant temperature. Component Location:The engine coolant temperature sensor is located on the thermostat housing. Conditions for Running...

Reason:SAE J1939 Multiplexing PGN Timeout Error – Abnormal Update Rate. The ECM expected information from a multiplexed device but did not receive it soon enough or did not receive it at all. Effect:At least one multiplexed device will not operate properly. Circuit Description:Normally, 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,...

Reason:SAE J1939 Multiplexing Configuration Error – Out of Calibration. The ECM expected information from a multiplexed device but only received a portion of the necessary information. Effect:At least one multiplexed device will not operate properly. Circuit Description:Normally, 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...

Reason:Aftertreatment Fuel Drain Valve – Mechanical System Not Responding Properly or Out of Adjustment. The aftertreatment fuel shutoff drain valve has been detected to be stuck closed. Effect:Active aftertreatment diesel particulate filter regeneration will be disabled. Circuit Description:The aftertreatment fuel drain valve is used to relieve the fuel pressure in the aftertreatment fuel injector supply line. Before active regeneration of the aftertreatment DPF, a diagnostic test on the system is performed. The aftertreatment fuel injector opens and relieves fuel pressure in the line. The aftertreatment fuel pressure sensor must be reading atmospheric pressure at this point in the test. The...