Volvo

The aftertreatment control module (ACM) uses the aftertreatment diesel exhaust fluid (DEF) dosing pressure sensor value to adjust and maintain DEF pressure at the DEF dosing valve by controlling DEF pump speed. If the pressure decreases below expected value when the pump is in initial pressure build-up mode or if the pressure increases above expected value when pump is in idle speed mode, the ACM considers DEF pressure outside of normal operating range and indicates a malfunction in a DEF dosing pressure sensor. Conditions for diagnostic trouble code (DTC):1) The voltage at pin A137:9 is below normal value Observable symptoms1)...

The aftertreatment control module (ACM) uses the aftertreatment diesel exhaust fluid (DEF) dosing pressure sensor value to adjust and maintain DEF pressure at the DEF dosing valve by controlling DEF pump speed. If the pressure decreases below expected value when the pump is in initial pressure build-up mode or if the pressure increases above expected value when pump is in idle speed mode, the ACM considers DEF pressure outside of normal operating range and indicates a malfunction in a DEF dosing pressure sensor. Conditions for diagnostic trouble code (DTC):1) The voltage at pin A137:7 is above normal value Observable symptoms1)...

The aftertreatment control module (ACM) uses the aftertreatment diesel exhaust fluid (DEF) dosing pressure sensor value to adjust and maintain DEF pressure at the DEF dosing valve by controlling DEF pump speed. If the pressure decreases below expected value when the pump is in initial pressure build-up mode or if the pressure increases above expected value when pump is in idle speed mode, the ACM considers DEF pressure outside of normal operating range and indicates a malfunction in a DEF dosing pressure sensor. Conditions for diagnostic trouble code (DTC):1) The voltage at pin A137:7 is below normal value Observable symptoms1)...

The aftertreatment control module (ACM) uses the aftertreatment diesel exhaust fluid (DEF) dosing pressure sensor value to adjust and maintain DEF pressure at the DEF dosing valve by controlling DEF pump speed. If the pressure decreases below expected value when the pump is in initial pressure build-up mode or if the pressure increases above expected value when pump is in idle speed mode, the ACM considers DEF pressure outside of normal operating range and indicates a malfunction in a DEF dosing pressure sensor. Conditions for diagnostic trouble code (DTC):1) Open circuit Observable symptoms1) No aftertreatment diesel exhaust fluid (DEF) dosage...

When ignition key is turned to OFF position the selective catalytic reduction (SCR) system enters afterrun mode. During afterrun, system attempts to drain diesel exhaust fluid (DEF) from the DEF dosing valve, DEF pump and DEF lines. Aftertreatment control module (ACM) activates DEF return valve by grounding the control wire (-). When the return valve is activated, the DEF reverses flow back to the tank, and DEF dosing pressure is expected to drop. If the dosing pressure does not drop or if it increases during afterrun, the return valve is considered to have a mechanical fault. Conditions for diagnostic trouble...