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Reason:Engine Fuel Pump Pressurizing Assembly 1 Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage or open circuit is detected at the fuel pump actuator circuit. Effect:Engine may run rough, may stop running, may not start, or may be difficult to start. Circuit Description:The circuit is a pulse-width modulation (PWM) driver in the engine control module (ECM) that controls the fuel pump actuator. The actuator is grounded in the ECM. The actuator is normally open. The PWM duty cycle to the fuel pump actuator depends on the difference between desired rail pressure and sensed rail pressure....

Reason:Aftertreatment Fuel Drain Valve Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the aftertreatment fuel drain valve circuit. 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. Component Location:The aftertreatment fuel drain valve is located in the aftertreatment fuel shutoff manifold. Conditions for Running the Diagnostics:This diagnostic runs when the aftertreatment fuel drain valve is commanded ON. Conditions for Setting the Fault Codes:The Engine Control Module (ECM) detected an open or short in...

Reason:Exhaust Gas Pressure – Data Valid but Above Normal Operating Range – Moderately Severe Level. High exhaust gas pressure has been detected by the exhaust gas pressure sensor. Effect:Possible reduced engine performance Circuit Description:The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust manifold. This information is used by the engine control module (ECM) to control emissions and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The exhaust...

Reason:Exhaust Gas Pressure – Data Valid but Above Normal Operating Range – Moderately Severe Level. High exhaust gas pressure has been detected by the exhaust gas pressure sensor. Effect:Possible reduced engine performance Circuit Description:The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust manifold. This information is used by the engine control module (ECM) to control emissions and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The exhaust...

Reason:Aftertreatment Outlet NOx Sensor – Abnormal Update Rate. No communications or an invalid data transfer rate detected on the J1939 data link between the ECM and the aftertreatment outlet Nox sensor. Effect:Possible reduced engine performance. Circuit Description:The 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...