Volvo SPN 5394 FMI 5 Aftertreatment DEF Dosing Valve- Current below normal or open circuit

bigrig

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Volvo SPN 5394 FMI 5 Aftertreatment DEF Dosing Valve- Current below normal or open circuit
This Fault Code is activated when a reduced NOx conversion is detected
When the DEF dosing valve duty cycle increases above allowed threshold and the DEF pump control value decreases below expected threshold, the ACM stops DEF dosing and reports a fault. The fault might be indication of electrical failure or blockage in DEF dosing valve or DEF supply line from the DEF tank.

Symptoms and Vehicle Effect

Excessive NOx emissions
Derating engine torque
No aftertreatment diesel exhaust fluid DEF dosage

Cause for Fault code

Open circuit Wiring harness damaged by rubbing with frame mostly its damage just under the ACM on DEF tank
Connector Plug damage inside
Failed DEF Injector
Failed DEF Dosing
Over fueling DEF
Aftertreatment diesel exhaust fluid DEF dosage valve
Dosage electronic control unit the DEF pump
Faults That result leaking or high hydrocarbons in muffler


Wiring Harness Damaged Video Its show for Mack Truck but its same as Volvo
 
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