Overview
CODE | REASON | EFFECT |
Fault Code: 5655 PID: SPN: 4364 FMI: 11/31 LAMP: Amber SRT: |
NOx conversion across the SCR catalyst is too low.
|
Possible reduced engine performance. |
Circuit Description
The engine control module (ECM) monitors the NOx concentration in the engine’s exhaust gases using an aftertreatment intake NOx sensor and an aftertreatment outlet NOx sensor. By comparing these two values, the ECM is able to determine the conversion efficiency of the SCR catalyst and dosing system.
Component Location
The SCR catalyst is located in the vehicle’s exhaust system, after the diesel particulate filter and decomposition tube.
Conditions for Running the Diagnostics
This diagnostic has to meet specific engine and aftertreatment conditions to run and complete.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the NOx conversion across the SCR catalyst was less than expected.
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.
- This fault code may cause possible derate related fault code to become active.
Conditions for Clearing the Fault Code
- It is necessary to use the “Reset All Faults” command in the recommended Cummins® electronic service tool or equivalent to clear this fault and extinguish the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp (MIL).
Shop Talk
Troubleshoot all other active NOx sensor and SCR dosing system related fault codes before this fault.
Possible causes of this fault code include:
Malfunctioning aftertreatment diesel exhaust fluid dosing system.
Exhaust system leaks
Malfunctioning SCR catalyst
Degraded, diluted, or incorrect diesel exhaust fluid
Diesel exhaust fluid deposits in the decomposition tube.
Troubleshooting Summary
- Fault Code 5655 requires that ALL solutions be performed
- Check for primary fault codes
- Aftertreatment diesel exhaust fluid is contaminated
- Aftertreatment exhaust system leaks
- Leaks in the aftertreatment diesel exhaust fluid dosing system
- Aftertreatment Diesel Exhaust Fluid Doser Pump Override test
- Aftertreatment diesel exhaust fluid dosing valve is malfunctioning
- Aftertreatment Outlet NOx Sensor Test
- Aftertreatment Intake NOx Sensor Test
- Aftertreatment SCR System Test
- Aftertreatment diesel exhaust fluid dosing system test failed
- Aftertreatment intake NOx sensor failed
- Aftertreatment outlet NOx sensor – Inspection
- Inspect both aftertreatment NOx sensors
- Aftertreatment SCR Catalyst Test Failed
- ECM calibration revision history check
Solution: S00007691
Verification
Conditions
- Turn keyswitch OFF.
Action
- This solution is information only.
- ALL solutions displayed for this fault code must be performed.
- Continue to perform the verifications of ALL solution steps listed for this fault code regardless if a given solution is within specification or out of specification.
- If redirected in this troubleshooting to another fault code or symptom it is required to come back to this fault code troubleshooting and complete every step.
Specification
- This solution is information only.
Linked Solutions
- None
Repair
- If a resolution is found in any solution for this fault code, continue performing ALL solutions listed for this fault code.
Validation
- None
Solution: S00000071
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:
- Aftertreatment NOx: 1885, 1887, 2771, 3228, 3232, 3545, 3583, 3649, 3681, 3682, 3717, 3718, 3725, 3748, 3749, 4452
- Aftertreatment outlet oxygen: 4749, 4751, 5656
- Aftertreatment intake oxygen: 4747, 4748
- Aftertreatment SCR: 3142, 3146, 3147, 3148, 3165, 4164, 4166, 4518, 4519, 4521, 4524, 4525, 6266, 6267, 6268, 8363
- Aftertreatment diesel exhaust fluid system: 1668, 1669, 1673, 1682, 3497, 3498, 3571, 3572, 3574, 3575, 4677, 4732, 4739, 5278
- Aftertreatment diesel exhaust fluid dosing unit: 3558, 3559
- Ambient air temperature: 249, 256, 2398
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Solution: S00000563
Verification
Conditions
- Turn keyswitch OFF.
Action
- Inspect the aftertreatment diesel exhaust fluid in the tank for signs of debris or contamination.
- Use a diesel exhaust fluid refractometer to measure the concentration of the diesel exhaust fluid in the tank.
Specification
- If there are signs of contaminates in the aftertreatment diesel exhaust fluid, then proceed to the Repair section.
Linked Solutions
- None
Repair
- Drain the diesel exhaust fluid tank, clean thoroughly and refill with pure diesel exhaust fluid.
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: S00001008
Verification
Conditions
- Engine running.
Action
- Visually inspect for leaks in the exhaust manifold to head.
- Visually inspect for leaks from the turbocharger to exhaust manifold.
- Visually inspect for leaks in the exhaust plumbing between the turbocharger outlet and the Aftertreatment DOC intake connection.
- Visually inspect the exhaust piping for leaks, cracks, and loose connections.
- Inspect for leaks at the aftertreatment DOC housing, sensor ports and connection points.
- Visually inspect the aftertreatment and SCR components for exhaust leaks.
Specification
- If there is any damage or leaks found in the exhaust system, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Replace the exhaust manifold.
- Repair or replace the exhaust plumbing.
Refer to OEM Service Manual
- Replace aftertreatment DOC.
- Replace the aftertreatment diesel particulate filter.
- Replace the aftertreatment SCR Catalyst.
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: S00000562
Verification
Conditions
- Reconnect all aftertreatment diesel exhaust fluid lines and electrical connectors to the dosing unit and aftertreatment diesel exhaust fluid tank if they have been previously disconnected during troubleshooting.
- Reconnect the aftertreatment diesel exhaust fluid dosing valve to the decomposition tube if it has been previously disconnected during troubleshooting.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Use the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid System Leak Test found under ECM Diagnostic Tests.
- While the test is running, inspect the diesel exhaust fluid tank connectors, diesel exhaust fluid dosing unit and dosing unit connectors, diesel exhaust fluid lines, and diesel exhaust fluid dosing valve for signs of external leaks.
Specification
- If a line, fitting, connection, or dosing unit is leaking, then a malfunction has been detected in the aftertreatment diesel exhaust fluid system or dosing unit.
Linked Solutions
- None
Repair
- Repair the source of the external diesel exhaust fluid leak.
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: S00002761
Verification
Conditions
- Reconnect all aftertreatment diesel exhaust fluid lines and electrical connectors to the dosing unit and aftertreatment diesel exhaust fluid tank if they have been previously disconnected during troubleshooting.
Action
- Remove the aftertreatment diesel exhaust fluid dosing valve from the decomposition tube.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
- Use the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test.
The Aftertreatment Diesel Exhaust Fluid Doser Pump Override test can only be ran twice before a key cycle needs to be performed.
Specification
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test meets the specification, then proceed to the next solution.
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test does not meet the specification, then proceed to the Linked Solutions section.
Linked Solutions
Click on the link below:
- Aftertreatment diesel exhaust fluid dosing valve is malfunctioning
Repair
- No additional action is required for this solution.
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: S00002764
Verification
Conditions
- Turn keyswitch OFF.
- Connect the recommended Cummins® electronic service tool or equivalent.
Action
- Clean the aftertreatment diesel exhaust fluid dosing valve.
- Turn keyswitch ON.
- Use the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test.
Specification
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test is not within specification, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Replace the aftertreatment diesel exhaust fluid dosing valve.
- Replace aftertreatment diesel exhaust fluid dosing unit.
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: S00010878
Verification
Conditions
- Reconnect previously disconnected components.
Specification
- If the Aftertreatment Outlet NOx Sensor Test does not pass, then proceed to the Repair section.
- If the Aftertreatment Outlet NOx Sensor Test does not complete, then reset the Search to Aftertreatment Outlet NOx Sensor Test did not complete.
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: S00010320
Verification
Conditions
- Reconnect previously disconnected components.
Specification
- If the Aftertreatment Intake NOx Sensor Test does not pass, then proceed to the Repair section.
- If the Aftertreatment Intake NOx Sensor Test does not complete, then reset the Search to Aftertreatment Intake NOx Sensor Test did not complete.
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: S00000541
Verification
Conditions
- Connect all components.
Action
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
- Use the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment SCR System Test.
If the Aftertreatment SCR System Test is not available on the recommended Cummins® electronic service tool or equivalent, update to the latest ECM Calibration Revision and then perform the Aftertreatment SCR System Test.
Specification
- If the Aftertreatment SCR System Test does not pass, then proceed to the Linked Solutions section.
If the Aftertreatment SCR System Test does not activate, then reset the Search to Aftertreatment SCR System Test does not activate.
If the Aftertreatment SCR System Test does not complete, then reset the Search to Aftertreatment SCR System Test does not complete.
If the Aftertreatment SCR System Test displays “Deposit Burn Failed”, the test should keep running and no repair action is required unless a Aftertreatment Intake or Outlet NOx sensor failure is detected.
Linked Solutions
- Aftertreatment diesel exhaust fluid dosing system test failed
- Aftertreatment intake NOx sensor failed
- Aftertreatment outlet NOx sensor – Inspection
- Inspect both aftertreatment NOx sensors
- Aftertreatment SCR catalyst test failed
Repair
- No additional action is required for this solution.
Validation
- None
Solution: S00000552
Verification
Conditions
- Turn keyswitch OFF.
Action
- Inspect the aftertreatment diesel exhaust fluid in the tank for signs of debris or contamination.
- Perform the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test.
Specification
- If there are signs of contaminates in the diesel exhaust fluid, then proceed to the Repair section.
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump override test displays FAILED, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Drain the diesel exhaust fluid tank, clean thoroughly and refill with pure diesel exhaust fluid.
Refer to OEM Service Manual
- For a Aftertreatment Diesel Exhaust Fluid Doser Pump override test displaying FAILED, then follow the repair instructions in the procedure.
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: S00000867
Verification
Conditions
- None
Action
- Verify that the aftertreatment intake NOx sensor is displayed as FAILED.
Specification
- If the SCR System test displays that the intake NOx sensor has FAILED, then proceed to the Repair section.
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: S00000567
Verification
Conditions
- Turn keyswitch OFF.
Action
- Inspect the decomposition tube for deposits.
- Visually inspect the aftertreatment diesel exhaust fluid tank connections for cracks or pitting.
Refer to OEM Service Manual
- Connect all aftertreatment diesel exhaust fluid lines and electrical connectors to the dosing unit and aftertreatment diesel exhaust fluid tank.
- Remove the aftertreatment diesel exhaust fluid dosing valve from the decomposition tube.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid System Leak Test found under ECM Diagnostic Tests.
- While the test is running, inspect the diesel exhaust fluid tank connectors, diesel exhaust fluid dosing unit and dosing unit connectors, diesel exhaust fluid lines, and diesel exhaust fluid dosing valve for signs of external leaks.
Specification
- If the aftertreatment diesel exhaust fluid dosing valve is not leaking and there are no deposits in the decomposition tube, then a malfunctioning aftertreatment outlet NOx sensor has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Replace the aftertreatment outlet NOx sensor.
- Replace the aftertreatment diesel exhaust fluid dosing valve.
- Clean and install the decomposition tube.
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: S00000566
Verification
Conditions
- Turn keyswitch OFF.
Action
- Inspect the decomposition tube for deposits.
- Inspect the aftertreatment diesel exhaust fluid tank connections for cracks or pitting.
Refer to OEM Service Manual
- Connect all aftertreatment diesel exhaust fluid lines and electrical connectors to the dosing unit and aftertreatment diesel exhaust fluid tank.
- Remove the aftertreatment diesel exhaust fluid dosing valve from the decomposition tube.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid System Leak Test found under ECM Diagnostic Tests.
- Verify proper sealing at all connection points, including diesel exhaust fluid tank, dosing unit, and dosing valve.
Specification
- If the aftertreatment diesel exhaust fluid dosing valve is not leaking and there are no deposits in the decomposition tube, then a malfunctioning aftertreatment intake NOx sensor and a malfunctioning aftertreatment outlet NOx sensor has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Replace the aftertreatment intake NOx sensor.
- Replace the aftertreatment outlet NOx sensor.
- Replace the aftertreatment diesel exhaust fluid dosing valve.
- Clean and install the decomposition tube.
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: S00000565
Verification
Conditions
- Reconnect all aftertreatment diesel exhaust fluid lines and electrical connectors to the dosing unit and aftertreatment diesel exhaust fluid tank if they have been previously disconnected during troubleshooting.
Action
The aftertreatment diesel exhaust fluid dosing valve must be removed and placed in a measuring container greater then 1.5 liter [50 oz] capacity to perform the Aftertreatment Diesel Exhaust Fluid Doser Pump Override test.
The Aftertreatment Diesel Exhaust Fluid Doser Pump Override test can only be ran twice before a key cycle needs to be performed.
- Remove the aftertreatment diesel exhaust fluid dosing valve from the decomposition tube.
- Turn keyswitch ON.
- Connect the recommended Cummins® electronic service tool or equivalent.
- Perform the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test.
Specification
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test is not within specification, then proceed to the Repair section.
- If the Aftertreatment Diesel Exhaust Fluid Doser Pump Override Test is within specification, then a malfunctioning aftertreatment SCR Catalyst has been detected.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Replace the aftertreatment diesel exhaust fluid dosing valve.
- Replace the aftertreatment SCR Catalyst.
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.