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Reason:Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Valve – Mechanical System Not Responding or Out of adjustment. A mechanical malfunction has been detected in the DEF dosing valve. Effect:Possible reduced engine performance. Circuit Description:The aftertreatment diesel exhaust fluid dosing valve is controlled by the ECM. When the engine control module (ECM) commands DEF dosing, the ECM sends a pulse width modulated (PWM) signal to the dosing valve, which opens the dosing valve and allows DEF to be sprayed into the exhaust stream. Component Location:The aftertreatment diesel exhaust fluid dosing valve is installed in the exhaust system. It is mounted directly to...

Reason:Aftertreatment Diesel Exhaust Fluid Pressure Sensor – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the aftertreatment diesel exhaust fluid pressure sensor circuit. Effect:Possible reduced engine performance Circuit Description:The Engine Control Module (ECM) provides a 5 volt supply and a ground to the aftertreatment diesel exhaust fluid pressure sensor. The pressure sensor provides a signal to the ECM on the sensor signal circuit. This sensor signal voltage changes, based on the aftertreatment diesel exhaust fluid pressure supplied by the dosing unit. The ECM will detect a low signal voltage at low diesel exhaust fluid pressures,...

Reason:Aftertreatment Diesel Exhaust Fluid Pressure Sensor – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the diesel exhaust fluid pressure sensor circuit. Effect:Possible reduced engine performance. Circuit Description:The Engine Control Module (ECM) provides a 5 volt supply and a ground to the aftertreatment diesel exhaust fluid pressure sensor. The pressure sensor provides a signal to the ECM on the sensor signal circuit. This sensor signal voltage changes, based on the aftertreatment diesel exhaust fluid pressure supplied by the dosing unit. The ECM will detect a low signal voltage at low diesel exhaust fluid pressures, and...

Reason:Aftertreatment Diesel Exhaust Fluid Pressure Sensor – Data Valid But Below Normal Operating Range – Moderately Severe Level. Low diesel exhaust fluid pressure has been detected in the dosing unit. Effect:Possible reduced engine performance. Circuit Description:The Engine Control Module (ECM) provides a 5 volt supply and a ground to the aftertreatment diesel exhaust fluid pressure sensor. The pressure sensor provides a signal to the ECM on the sensor signal circuit. This sensor signal voltage changes, based on the aftertreatment diesel exhaust fluid pressure supplied by the dosing unit. The ECM will detect a low signal voltage at low diesel exhaust...

Reason:Aftertreatment Diesel Exhaust Fluid Pressure Sensor – Data Valid But Below Normal Operating Range – Moderately Severe Level. Low diesel exhaust fluid pressure has been detected in the dosing unit. Effect:Possible reduced engine performance. Circuit Description:The Engine Control Module (ECM) provides a 5 volt supply and a ground to the aftertreatment diesel exhaust fluid pressure sensor. The pressure sensor provides a signal to the ECM on the sensor signal circuit. This sensor signal voltage changes, based on the aftertreatment diesel exhaust fluid pressure supplied by the dosing unit. The ECM will detect a low signal voltage at low diesel exhaust...