Volvo

Conditions for diagnostic trouble code (DTC):
1) Short circuit to battery voltage

Probable cause
1) Wiring harness
2) R23B (Hose heater)

Conditions for diagnostic trouble code (DTC):
1) Short circuit to ground

Probable cause
1) Wiring harness
2) R23B (Hose heater)

Conditions for diagnostic trouble code (DTC):
1) Open circuit

Probable cause
1) Wiring harness
2) R23B (Hose heater)

This diagnostic trouble code (DTC) indicates a malfunction at the diesel exhaust fluid (DEF) line heater 3. The DEF lines and line connections between the DEF tank and DEF pump are electrically heated by the DEF line heater 3. The DEF line heater 3 is normally OFF and is commended ON by the aftertreatment control module (ACM) when the ambient air temperature (AAT) and DEF tank temperature are below calibrated threshold. The ACM controls the DEF heater 3 by supplying battery voltage to the common voltage supply circuit and grounding control wire (-) circuit using pulse width modulated signal.

Conditions for diagnostic trouble code (DTC):
1) The voltage at pin A137:20 is above normal value

Observable symptoms
1) Ammonia smell can occur if the aftertreatment diesel exhaust fluid (DEF) warmed too much

Probable cause
1) Short circuit to voltage supply, Control wire (-)
2) Short circuit to 5V, Control wire (-)
3) Wiring harness
4) Aftertreatment Diesel Exhaust Fluid (DEF) Line Heater 3

This diagnostic trouble code (DTC) indicates a malfunction at the diesel exhaust fluid (DEF) line heater 3. The DEF lines and line connections between the DEF tank and DEF pump are electrically heated by the DEF line heater 3. The DEF line heater 3 is normally OFF and is commended ON by the aftertreatment control module (ACM) when the ambient air temperature (AAT) and DEF tank temperature are below calibrated threshold. The ACM controls the DEF heater 3 by supplying battery voltage to the common voltage supply circuit and grounding control wire (-) circuit using pulse width modulated signal.

Conditions for diagnostic trouble code (DTC):
1) The voltage at pin A137:20 is below normal value

Observable symptoms
1) Ammonia smell can occur if the aftertreatment diesel exhaust fluid (DEF) warmed too much

Probable cause
1) Short circuit to ground, Control wire (-)
2) Wiring harness
3) Aftertreatment Diesel Exhaust Fluid (DEF) Line Heater 3

This diagnostic trouble code (DTC) indicates a malfunction at the diesel exhaust fluid (DEF) line heater 3. The DEF lines and line connections between the DEF tank and DEF pump are electrically heated by the DEF line heater 3. The DEF line heater 3 is normally OFF and is commended ON by the aftertreatment control module (ACM) when the ambient air temperature (AAT) and DEF tank temperature are below calibrated threshold. The ACM controls the DEF heater 3 by supplying battery voltage to the common voltage supply circuit and grounding control wire (-) circuit using pulse width modulated signal.

Conditions for diagnostic trouble code (DTC):
1) Open circuit:

Observable symptoms
1) None

Probable cause
1) Open circuit, Control wire
2) Open circuit, Common voltage supply
3) Wiring harness
4) Aftertreatment Diesel Exhaust Fluid (DEF) Line Heater 3

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) Aftertreatment Diesel Exhaust Fluid (DEF) Pump Motor Speed Below normal

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

Probable cause
1) Frozen Aftertreatment Diesel Exhaust Fluid (DEF) Pump
2) Restricted Aftertreatment Diesel Exhaust Fluid (DEF) Pump
3) Aftertreatment Diesel Exhaust Fluid (DEF) Pump

Detailed information
1) Possible engine de-rate

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 A137:8 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 Diesel Exhaust Fluid (DEF) Pump
5) Aftertreatment Control Module (ACM)

Detailed information
1) Possible engine de-rate

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 A137:8 is below normal value

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

Probable cause
1) Short circuit to ground, Control wire (-)
2) Wiring harness
3) Aftertreatment Diesel Exhaust Fluid (DEF) Pump
4) Aftertreatment Control Module (ACM)

Detailed information
1) Malfunction indicator lamp (MIL) illuminated
2) Possible engine de-rate