Volvo

When the ignition key is switched to the RUN position, battery voltage is supplied though fuse 64 to the aftertreatment control module (ACM).

Conditions for diagnostic trouble code (DTC):
1) Ignition switch voltage shorted low

Probable cause
1) Chassis Harness
2) Cab harness
3) Fuse: F69

Aftertreatment Control Module (ACM) monitors DEF tank temperature and uses it to control the Aftertreatment DEF Tank Heater valve to keep the DEF from freezing.
This temperature monitoring is also used to avoid stopped DEF dosing due to high DEF tank temperatures. If the DEF temperature is too high, reverse flow will be activated, if the temperature stays high for a short duration, a DTC is set.

Conditions for diagnostic trouble code (DTC):
1) DEF Temperature above 70??C (158??F)

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

Probable cause
1) Extreme driving conditions (High ambient temperature)
2) DEF Tank too close to hot object
3) DEF Tank heating valve stuck open
4) DEF Tank Heating Valve installed backwards
5) Aftertreatment diesel exhaust fluid (DEF) tank, Temperature Sensor

Aftertreatment Control Module (ACM) monitors DEF tank temperature and uses it to control the Aftertreatment DEF Tank Heater valve to keep the DEF from freezing.
This temperature monitoring is also used to avoid stopped DEF dosing due to high DEF tank temperatures. If the DEF temperature is too high, reverse flow will be activated, if the temperature stays high for a short duration, a DTC is set.

Conditions for diagnostic trouble code (DTC):
1) The temperature in the tank is below normal

Probable cause
1) Aftertreatment diesel exhaust fluid (DEF) tank, Temperature Sensor
2) Wiring harness
3) Aftertreatment diesel exhaust fluid (DEF) tank heater valve
4) DEF Tank Heating Valve installed backwards

Aftertreatment Control Module (ACM) monitors DEF tank temperature and uses it to control the Aftertreatment DEF Tank Heater valve to keep the DEF from freezing.
This temperature monitoring is also used to avoid stopped DEF dosing due to high DEF tank temperatures. If the DEF temperature is too high, reverse flow will be activated, if the temperature stays high for a short duration, a DTC is set.

Conditions for diagnostic trouble code (DTC):
1) Short circuit to ground in the component or wiring
2) Short circuit to lower voltage

Observable symptoms
1) None

Probable cause
1) Connector
2) Wiring harness
3) Short circuit to ground, Signal wire
4) Aftertreatment diesel exhaust fluid (DEF) tank, Temperature Sensor

Aftertreatment Control Module (ACM) monitors DEF tank temperature and uses it to control the Aftertreatment DEF Tank Heater valve to keep the DEF from freezing.
This temperature monitoring is also used to avoid stopped DEF dosing due to high DEF tank temperatures. If the DEF temperature is too high, reverse flow will be activated, if the temperature stays high for a short duration, a DTC is set.

Conditions for diagnostic trouble code (DTC):
1) Open circuit between Electronic Control Unit and Sensor

Observable symptoms
1) Engine de-rated

Probable cause
1) Connector
2) Wiring harness
3) Short circuit to higher voltage, Signal wire
4) Open circuit on signal wire
5) Open circuit, Ground wire
6) Aftertreatment diesel exhaust fluid (DEF) tank, Temperature Sensor

Conditions for diagnostic trouble code (DTC):
1) Insufficient aftertreatment diesel exhaust fluid (DEF) dosage

Observable symptoms
1) Smell of ammonia

Probable cause
1) Aftertreatment diesel exhaust fluid (DEF) dosage valve
2) Aftertreatment selective catalytic reduction (SCR) catalyst

This function is used to determine the level of soot in the diesel particulate filter (DPF). This is done by using four different signal/parameters; estimated driving distance since last aftertreatment DPF regeneration, the time since last regeneration, fuel consumption and the aftertreatment DPF pressure. When this diagnostic trouble code (DTC) is set the filter needs servicing due to high level of soot or the aftertreatment DPF regeneration process does not function properly.

Conditions for diagnostic trouble code (DTC):
1) Moderately high soot load
2) Aftertreatment diesel particulate filter (DPF) soot load ratio more than 140 %

Observable symptoms
1) Low Power

Probable cause
1) Regeneration process is not functioning
2) Regeneration inhibited, driver has not allowed regeneration to take place
3) Aftertreatment Hydrocarbon Doser
4) Catalyst

Detailed information
1) Engine control module (ECM) commands the exhaust gas recirculation (EGR) valve to close when the aftertreatment diesel particulate filter (DPF) soot load ratio is more than 140 %
2) Medium to high derate

This diagnostic function monitors the aftertreatment DPF temperature sensors and DPF soot level during normal operation. Based upon the operating conditions and DPF soot level the ECU decides if the engine should be de-rated in order to protect the DPF system components.
This diagnostic trouble code (DTC) can only occur during normal operating conditions, aftertreatment diesel particulate filter (DPF) regeneration process not active. In some cases extreme driving conditions can cause soot in the DPF to oxidize at an unacceptable rate and cause DPF damage.

Conditions for diagnostic trouble code (DTC):
1) Overheating the DPF due to soot oxidation during extreme driving conditions
2) Aftertreatment diesel particulate filter (DPF) exhaust temperatures are higher than expected for the existing conditions

Observable symptoms
1) Low Power

Probable cause
1) Extreme driving conditions
2) Regeneration inhibited, driver has not allowed regeneration to take place
3) Regeneration process is not functioning
4) Charge air system leakage
5) Aftertreatment Hydrocarbon Doser, Leakage
6) Discharge recirculation valve open

Detailed information
1) Activation
2) Engine de-rated, medium to high

This function is used to determine the level of soot in the diesel particulate filter (DPF). This is done by using four different signal/parameters; estimated driving distance since last aftertreatment DPF regeneration, the time since last regeneration, fuel consumption and the aftertreatment DPF pressure. When this diagnostic trouble code (DTC) is set the filter needs servicing due to high level of soot or the aftertreatment DPF regeneration process does not function properly.

Conditions for diagnostic trouble code (DTC):
1) Critically high soot load
2) Aftertreatment diesel particulate filter (DPF) soot load ratio more than 170 %

Observable symptoms
1) Low Power

Probable cause
1) Aftertreatment Hydrocarbon Doser
2) Catalyst
3) Regeneration process is not functioning
4) Regeneration inhibited, driver has not allowed regeneration to take place

Detailed information
1) Activation
2) High derate with potentional engine shutdown
3) EGR valve commanded closed