Overview
| CODE | REASON | EFFECT |
| Fault Code: 3681 PID: SPN: 3228 FMI: 2/2 LAMP: Amber SRT: |
The aftertreatment outlet NOx sensor indicates that the power supply to the sensor is incorrect.
|
None on performance. |
Circuit Description
The aftertreatment outlet NOx (nitrogen oxides) sensor is a smart device and communicates with the engine control module (ECM) via the J1939 data link. The aftertreatment outlet NOx sensor performs its own internal diagnostics and reports malfunctions back to the primary ECM using the J1939 data link. The NOx sensor is permanently attached to the NOx control module. They are serviced as a single component and can not be replaced individually. The aftertreatment outlet NOx sensor is used to measure the NOx emissions at the outlet of the aftertreatment system.
Component Location
The aftertreatment outlet NOx sensor location can vary depending on engine application. It is usually located in the exhaust system at the outlet of the selective catalytic reduction (SCR) catalyst.
Conditions for Running the Diagnostics
This diagnostic runs when the aftertreatment SCR outlet temperature has been above 200°C [392° F] for a calibratable period of time while the engine is running.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the power supply to the outlet NOx sensor was above or below a calibrated threshold.
Action Taken When the Fault Code is Active
- The ECM illuminates the amber CHECK ENGINE lamp and/or malfunction indicator lamp (MIL) after the diagnostic fails on two consecutive trips.
Conditions for Clearing the Fault Code
- To validate the repair, start and operate the engine to raise exhaust temperatures. This can be done by either driving the vehicle or initiating a stationary regeneration using the recommended Cummins® electronic service tool or equivalent.
- The aftertreatment SCR outlet temperature must be above 200° C [392° F] for 60 seconds before the aftertreatment outlet NOx sensor can run its internal diagnostics.
- The aftertreatment diesel oxidation catalyst intake temperature must be above 200°C [392°F] for 2 minutes before the aftertreatment intake NOx sensor can run its internal diagnostics.
- The fault code status displayed by the recommended Cummins® electronic service tool or equivalent will change to INACTIVE immediately after the diagnostic runs and passes.
- The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
- 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.
- The “Reset All Faults” command in the recommended Cummins® electronic service tool or equivalent can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk
Possible causes of this fault code include:
Short to battery or ground in the OEM harness
Open NOx sensor power supply circuit in the OEM harness
- Incorrect system voltage set-up in the recommended Cummins® electronic service tool or equivalent.
Internal malfunction of the outlet NOx sensor
The NOx sensor part number is incorrect.
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.
Troubleshooting Summary
- Check for primary fault codes
- Low battery voltage
- Battery load test
- Ground inspection
- Incorrect adjustable parameter setting
- Aftertreatment outlet NOx sensor voltage check
- Battery circuit fuse has open circuit
- Battery or battery cables are malfunctioning
- Aftertreatment outlet NOx sensor has incorrect voltage
- Aftertreatment outlet NOx sensor open circuit
- Circuit Load Test
- ECM calibration revision history check
Solution: S00000292
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Use the recommended Cummins® electronic service tool or equivalent to read the fault codes.
Specification
Before troubleshooting this fault code, troubleshoot any fault code that is active or has more than one inactive count within the last 25 engine operating hours from the following list:
- Voltage: 441, 442, 596, 597, 598, 6256
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Solution: S00011171
Verification
Conditions
- Turn keyswitch OFF.
Action
- Visually inspect the batteries and the battery cable connections for corrosion.
- Measure the voltage from the positive (+) battery terminal to the negative (-) battery terminal.
- If this vehicle has been repaired within the last 30 days for the same fault code, then proceed to the Linked Solutions section.
Specification
- If the battery voltage is at least 10.8 VDC (12 volt systems) or 21.6 VDC (24 volt systems), then proceed to the Linked Solutions section.
- If the battery voltage is below 10.8 VDC (12 volt systems) or 21.6 VDC (24 volt systems), then proceed to the Repair section.
- If the battery or battery cables show signs of corrosion or damage, then proceed to the Repair Section.
Repair
Repair or replace only the components that were found to be out of specification.
- Charge or replace the batteries.
Refer to OEM Service Manual
- Clean corrosion or tighten battery cable connections.
Refer to OEM Service Manual
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00001379
Verification
Conditions
- Turn keyswitch OFF.
Action
- Disconnect the batteries from each other.
- Connect a load tester separately to each battery.
- Measure the voltage from the positive (+) battery terminal to the negative (-) battery terminal.
Specification
- For a 12 volt system, proceed to the Repair section if the battery voltage is below the following specification: 11 VDC
- For a 24 volt system, proceed to the Repair section if the battery voltage is below the following specification: 22 VDC
Linked Solutions
- None
Repair
- Charge or replace the batteries.
Refer to OEM Service Manual
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000754
Verification
Conditions
- Turn keyswitch OFF.
Action
- Visually inspect the ECM ground for damage, corrosion and loose connections.
- Visually inspect the aftertreatment interface wiring harness ground for damage, corrosion and loose connections.
- Visually inspect the OEM wiring harness ground for damage, corrosion and loose connections.
- Visually inspect the grounds for proper routing.
Specification
- If damage, corrosion or incorrect routing of grounds are found, then proceed to the Repair section
Linked Solutions
- None
Repair
- Clean or replace connections.
Refer to OEM Service Manual
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000886
Verification
Conditions
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Verify the Electrical System Voltage setting is correct for the engine configuration with the recommended Cummins® electronic service tool or equivalent.
Specification
- If the Electrical System Voltage setting does not match the measured voltage, then the incorrect adjustable parameter is configured.
Linked Solutions
- None
Repair
- Use the recommended Cummins® electronic service tool or equivalent.
- Configure the electrical system voltage to match the engine configuration.
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000869
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the aftertreatment outlet NOx sensor from the OEM wiring harness.
Action
- Inspect the pins and connectors for damage.
- Turn keyswitch ON.
- Measure the voltage from the aftertreatment outlet NOx sensor battery voltage SUPPLY pin to the aftertreatment outlet NOx sensor RETURN pin of the OEM wiring harness connector.
- Measure the battery voltage during keyswitch ON and then during cranking conditions.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- Proceed to the Linked Solutions section if the voltage is not within the following specification of battery voltage: 1 VDC
- Proceed to the Repair section if the voltage is within the following specification of battery voltage: 1 VDC
Linked Solutions
- Battery circuit fuse has open circuit
- Battery or battery cables are malfunctioning
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000870
Verification
Conditions
- Turn keyswitch OFF.
Action
- Visually inspect the batteries and the battery cable connections for corrosion.
- Check the battery voltage.
Specification
- If the voltage at the battery terminal is at least 12 VDC (24 VDC for a 24 volt system), then check the fuse to ensure they are installed correctly, not blown, damaged, corroded, or improperly seated.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Clean corrosion or tighten battery cable connections.
Refer to OEM Service Manual
- Replace the fuse.
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000871
Verification
Conditions
- Turn keyswitch ON.
Action
- Measure the battery voltage during keyswitch ON and then during cranking conditions.
- Visually inspect the batteries and the battery cable connections for corrosion.
- Check add-on components or the accessory wiring at the (+) battery terminal.
- If the engine cranks, but will not start then disconnect the battery supply connector from the ECM.
- Measure the voltage from the battery voltage SUPPLY to the battery voltage RETURN on the OEM side of the ECM battery supply connector.
Specification
- If the voltage at the battery is less than 10 VDC (20 VDC for 24 Volt systems), then a malfunctioning battery has been detected.
- A malfunctioning fuse or OEM wiring harness has been detected if the voltage at the OEM side of the battery supply connector is not within the following specification of battery voltage: 0.1 VDC
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Charge or replace the battery.
- Replace the fuse.
- Repair or replace the OEM wiring harness.
Validation
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
Solution: S00000882
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the aftertreatment outlet NOx sensor from the OEM wiring harness.
Action
- Inspect the pins and connectors for damage.
- Verify the correct aftertreatment outlet NOx sensor is installed for engine configuration (12 or 24 volt).
- Visually verify that the OEM fuses are not damaged or malfunctioning.
- Turn keyswitch ON.
- Measure the voltage from the aftertreatment outlet NOx sensor battery voltage SUPPLY pin to the aftertreatment outlet NOx sensor RETURN pin of the OEM wiring harness connector.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- Proceed to the next solution if voltage is within the following specification of battery voltage: 1 VDC
- Proceed to the Linked Solutions section if the voltage is not within the following specification of battery voltage: 1 VDC
Linked Solutions
Click on the link below:
- Aftertreatment outlet NOx sensor open circuit
Repair
- No additional action is required for this solution.
Validation
- None
Solution: S00000883
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect the aftertreatment outlet NOx sensor from the OEM wiring harness.
Action
- Inspect the pins and connectors for damage.
- Turn keyswitch ON.
- Measure the voltage from the aftertreatment outlet NOx sensor battery voltage SUPPLY pin of the OEM wiring harness to the engine block ground.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- An open circuit or high resistance has been detected in the aftertreatment outlet NOx sensor battery voltage RETURN circuit if the voltage is within the following specification of battery voltage: 1 VDC
- An open circuit or high resistance has been detected in the aftertreatment outlet NOx sensor battery voltage SUPPLY circuit if the voltage is not within the following specification of battery voltage: 1 VDC
Linked Solutions
- None
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00011049
Verification
Conditions
- Turn keyswitch OFF.
- Disconnect all components on the wiring circuit being tested.
Action
This test is NOT for checking the J1939 data link (+) and (-) pins since it may cause damage to the J1939 smart devices or sensors.
This test is NOT for checking the OEM wiring harness since it may cause damage to OEM smart devices or sensors.
- Perform the Circuit Load Test for the circuit being tested.
- Refer to the circuit diagram or wiring diagram for connector pin identification.
Specification
- If the voltage drop is not within specification, then a malfunctioning wiring harness has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Repair or replace the engine wiring harness.
- Repair or replace the OEM wiring harness.
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
Solution: S00000443
Verification
Conditions
- Connect all components.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Use the recommended Cummins® electronic service tool or equivalent to read the fault codes.
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revision listed in the ECM calibration revision history for applicable changes.
Specification
- If a calibration update for this fault code is available, the ECM calibration revision must be that revision or higher.
Linked Solutions
- None
Repair
- Prior to downloading the ECM calibration, check to see that all job images and all other troubleshooting has been documented as downloading an ECM calibration will remove the fault codes on the ECM.
- Download the updated ECM calibration code.
Validation
- Connect all components
- Connect the recommended Cummins® electronic service tool or equivalent.
- Disable the fault code.
- Operate the engine within the «Conditions for Clearing the Fault Code» found in the Overview section of the troubleshooting procedure.
- Verify that the fault code is no longer active.
- Check ECM Calibration Revision History
- Use the recommended Cummins® electronic service tool or equivalent to find the current ECM code and revision number in the ECM.
- Compare the ECM code and revision number in the ECM to the calibration revisions listed in the ECM Calibration Revision History Database for applicable changes related to this fault code.
- Refer to ECM Calibration Revision History Database.
If all steps have been completed and no root cause has been identified, then follow the technical escalation process.