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Reason:
Aftertreatment SCR Intake Temperature Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the SCR intake temperature sensor circuit.

Effect:
Possible reduced engine performance.

Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intake temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually.

Component Location:
The aftertreatment SCR temperature sensor module is mounted by the OEM near the aftertreatment SCR catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position and the engine is running

Conditions for Setting the Fault Codes:
The aftertreatment SCR temperature sensor module reported the aftertreatment SCR intake temperature signal was out of range low.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.
2) Diesel exhaust fluid injection into the aftertreatment system is disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
N/A

Possible Causes:
1) A malfunctioning aftertreatment SCR intake temperature sensor

Reason:
Aftertreatment SCR Outlet Temperature Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the SCR outlet temperature sensor circuit.

Effect:
Possible reduced engine performance

Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually.

Component Location:
The aftertreatment SCR temperature sensor module is mounted on the aftertreatment SCR catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running

Conditions for Setting the Fault Codes:
The aftertreatment SCR temperature sensor module reported the aftertreatment SCR outlet temperature signal was out of range high.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) Diesel exhaust fluid injection into the aftertreatment system is disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Causes:
1) A malfunctioning aftertreatment SCR outlet temperature sensor

Reason:
Aftertreatment SCR Outlet Temperature Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the SCR outlet temperature sensor circuit.

Effect:
Possible reduced engine performance.

Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually.

Component Location:
The aftertreatment SCR temperature sensor module is mounted on the aftertreatment SCR catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running

Conditions for Setting the Fault Codes:
The aftertreatment SCR temperature sensor module reported the aftertreatment SCR outlet temperature signal was out of range low.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) Diesel exhaust fluid injection into the aftertreatment system is disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM. For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Causes:
1) A malfunctioning aftertreatment SCR outlet temperature sensor

Reason:
Aftertreatment SCR Outlet Temperature Sensor – Data Erratic, Intermittent, or Incorrect. The SCR outlet temperature sensor is not changing with engine operating conditions.

Effect:
Possible reduced engine performance

Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually.

Component Location:
The aftertreatment SCR temperature sensor module is mounted on the aftertreatment SCR catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs when the exhaust gas temperature sensors are compared to other engine temperatures during engine operation. The engine coolant temperature must be above 60°C [140°F] before the diagnostic will run.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the aftertreatment SCR outlet temperature sensor signal was irrational for more than 5 minutes.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp (MIL) after the diagnostic fails on two consecutive trips.
2) A default value for the SCR catalyst outlet temperature is used.
3) Diesel exhaust fluid injection into the aftertreatment system is disabled.
4) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and let it idle for up to 5 minutes.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Causes:
1) A malfunctioning aftertreatment SCR outlet temperature sensor

Reason:
Aftertreatment SCR Outlet Temperature – Data Valid But Above Normal Operational Range – Most Severe Level. The selective catalytic reduction (SCR) outlet temperature sensor reading has exceeded the maximum temperature limit.

Effect:
Possible reduced engine performance.

Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart device that communicates with the engine control module via the J1939 data link. The aftertreatment SCR temperature sensor module performs its own internal diagnostics and reports malfunctions back to the engine control module using the J1939 data link. The aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes are permanently attached to the aftertreatment SCR temperature sensor module and can not be replaced individually.

Component Location:
The aftertreatment SCR temperature sensor module is mounted on the aftertreatment SCR catalyst.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the temperature at the SCR catalyst outlet temperature sensor was greater than 800°C [1472°F] for more than 20 seconds.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the red STOP ENGINE lamp immediately after the diagnostic runs and fails.
2) The engine will be shut down if the Engine Protection Shutdown feature is enabled.
3) Diesel exhaust fluid injection into the aftertreatment system is disabled.

Conditions for Clearing the Fault Code:
It is necessary to use the “Reset All Faults” command in INSITE™ electronic service tool to clear this fault. To validate the repair, perform a key cycle, start the engine and idle. Use INSITE™ electronic service tool to perform the aftertreatment SCR system cleaning test found in the ECM diagnostic tests.

Shop Talk:
This fault will go inactive immediately after the SCR outlet temperature drops below the warning limit, and will likely be inactive at the time of diagnosis. For these reasons this troubleshooting tree must be used for both active and inactive fault codes.

Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

Possible Causes:
1) Malfunctioning SCR catalyst
2) Degraded, diluted, or incorrect diesel exhaust fluid
3) Malfunctioning in-range SCR outlet temperature sensor

Reason:
Aftertreatment Doser – Data Valid But Below Normal Operating Range – Moderately Severe Level. The ECM detects that the aftertreatment fuel injector has used up all compensation.

Effect:
Possible frequent need for aftertreatment regeneration

Circuit Description:
The aftertreatment fuel injector is electronically controlled by the engine electronic control module (ECM) through a pulse width modulated (PWM) signal. The amount of fuel injected is determined by how long the PWM signal to the injector is on.

Component Location:
The aftertreatment fuel injector is installed in the exhaust system in the turbocharger adapter pipe. The aftertreatment fuel pressure sensor and aftertreatment fuel shutoff valve are installed in the shutoff valve manifold. The aftertreatment purge air actuator is located above the shutoff valve manifold.

Conditions for Running the Diagnostics:
This diagnostic runs during active regeneration of the aftertreatment diesel particulate filter.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the aftertreatment fuel injector could not inject enough fuel for active regeneration of the aftertreatment diesel particulate filter.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and perform the INSITE™ electronic service tool Aftertreatment Diesel Particulate Filter Regeneration Test.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
N/A

Possible Causes:
1) A dirty or damaged aftertreatment fuel injector

Reason:
Injector Solenoid Driver Cylinder 1 Circuit – Current Below Normal or Open Circuit. Current detected at injector 1 when voltage is turned OFF.

Effect:
Possible reduced engine performance

Circuit Description:
The injector solenoid valves control fueling quantity and injection timing. The engine control module (ECM) energizes the solenoid by closing a high-side and a low-side switch. Each injector circuit has a dedicated low side switch that completes the circuit path to ground inside the ECM.

Component Location:
The engine harness connects the ECM to the pass-through connector(s) that are located in the rocker housing. Internal injector harnesses are located under the valve cover and connect the injectors to the engine harness at the pass-through connector(s).

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected a circuit error on an injector(s) circuit. The ECM will disable the injection event for the affected injector(s) circuit if there is excessive current.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) The injector will be disabled for the malfunctioning cylinder.
3) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
4) Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
If more than one injector fault code is occurring, and the faults occur for injector circuits in the same bank, a short circuit exists. If a fault condition is intermittent, and especially if more than one injector fault code is occurring, look for a wire harness that can short to components inside the rocker housing or a short circuit to ground in the injector solenoid. When looking for short circuits in the injector harnesses, pay particular attention to the wire insulation, making sure there are no shorts to a rocker lever.

An intermittent short can result if the wiring harness insulation rubs through near a rocker lever. An intermittent short can cause a single injector fault code. If the fault(s) occur intermittently, the engine can exhibit a misfire even if the injector circuit fault code does not always register. If a single cylinder exhibits misfires, look for an open circuit problem. If several cylinders on the same bank exhibit misfires, look for a short circuit anywhere in the bank of cylinders.

Possible causes of a single injector fault include:
1) Open circuit in the engine harness(es) or injector solenoid
2) High resistance in a single injector or injector solenoid
3) Extremely low resistance in an injector solenoid (injector shorted internally but not to ground)
4) Malfunctioning or damaged ECM.

Possible causes of multiple injector fault codes in the same bank of injectors include:
1) Short circuit in the engine harness(es) – either shorts to ground or to other wires in the engine harness
2) Short circuit in any of the three injectors in the bank – shorts to ground Malfunctioning or damaged ECM.

Same Bank Fault Codes:
1) Bank 1 – Front Bank: Fault Codes 322, 324, 331
2) Bank 2 – Rear Bank: Fault Codes 323, 325, 332