VOLVOUU All Engines (2010 Emissions) Fault Code: SPN 5394 FMI 3 PID: PSID 89 Aftertreatment DEF Dosing Valve

When the aftertreatment selective catalytic reduction (SCR) system operates under normal conditions, the aftertreatment control module (ACM) monitors diesel exhaust fluid (DEF) dosing valve duty cycle and DEF pump control value. 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.

Conditions for diagnostic trouble code (DTC):
1) The voltage at pin Pin A137:36 is above normal value

Observable symptoms
1) No aftertreatment diesel exhaust fluid (DEF) dosage

Probable cause
1) Short circuit to voltage supply, Control wire (-)
2) Short circuit to 5V, Control wire (-)
3) Wiring harness
4) Aftertreatment DEF dosing valve
5) Aftertreatment Control Module (ACM)

Detailed information
1) Possible engine de-rate