EGR Valve Controller – Out of Calibration
Overview
| CODE | REASON | EFFECT |
| Fault Code: 1896 PID: S146 SPN: 2791 FMI: 13/13 LAMP: Amber SRT: |
The EGR valve has failed the automatic calibration procedure at initial key ON.
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Possible reduced engine performance.
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EGR Valve Circuit
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Circuit Description
The exhaust gas recirculation (EGR) valve is controlled by a brushless motor located on top of the EGR valve. The EGR valve motor uses three different motor legs to move the valve through its range of motion. The ECM uses the EGR motor A, B, and C wires to command the EGR valve to the appropriate position in order to meet EGR flow targets.The EGR valve motor contains three position sensors that detect the location of the EGR valve. These sensors report the position of the valve back to the ECM over the EGR valve position A, B, and C wires.
Component Location
The EGR Valve and EGR Differential Pressure Sensor location varies depending on engine model.
Conditions for Running the Diagnostics
This diagnostic runs at initial key ON and occasionally during normal engine operation after the EGR valve is commanded closed.
Conditions for Setting the Fault Codes
The Engine Control Module (ECM) detected the EGR valve failed the autozero span check.
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.
Exhaust gas recirculation (EGR) valve operation will be disabled.
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
- To validate the repair, bring the engine up to operating temperature and run it in normal loaded conditions for 15 minutes.
- Turn the key switch OFF and allow the ECM to completely powerdown.
- Start and idle the engine for 1 minute
- 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 after the diagnostic runs and passes.
- For On-Board Diagnostics (OBD) engines, the ECM will turn off the 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.
When the keyswitch is initially turned ON and at various times during engine operation, the closed position of the EGR valve is checked. This diagnostic checks to make sure the EGR valve is not stuck open.
The EGR valve will close when the fault code is active. The fault code will remain active until the next key cycle.
The aftertreatment system must be inspected after making the appropriate repair outlined in this fault code troubleshooting tree. Progressive damage to the aftertreatment system may have occurred. Perform the Snap-Acceleration Test to check for a malfunctioning diesel particulate filter.
Troubleshooting Summary
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:
- Intake manifold: 125, 3361
Linked Solutions
- None
Repair
- Perform a search on the appropriate fault codes.
Validation
- None
Verification
Conditions
- Turn keyswitch OFF.
Action
- Turn keyswitch OFF for 10 seconds and then turn the keyswitch ON.
- Connect the recommended Cummins electronic service tool or equivalent.
- Use the recommended Cummins electronic service tool or equivalent to read the fault codes.
Specification
- A malfunctioning EGR valve has been detected if a fault code from the following list is active or has more than one inactive count within the last 25 engine operating hours: 1896.
Linked Solutions
- None
Repair
If the EGR valve has been replaced within the last 90 days, follow your technical escalation process PRIOR to performing any of the repair actions listed below:
- Replace the EGR valve.
- Perform the Snap Acceleration – Aftertreatment Connected Test.
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.
Verification
Conditions
- Turn keyswitch OFF.
Action
- Inspect the intake plumbing for possible air leaks.
Specification
- If a leak is found, then proceed to the Repair section.
Linked Solutions
- None
Repair
- Repair or replace the leaking components.
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.
Verification
Conditions
- Turn keyswitch OFF.
Action
- Perform the Charge Air Cooler Leak Test.
Specification
- If a leak is found, then proceed to the Repair section.
Linked Solutions
- None
Repair
Repair or replace only the components that were found to be out of specification.
- Repair or replace the charge air cooler.
- Repair or replace the charge air cooler hoses.
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.
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.
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.
- Verify all preceding solution verifications for this fault code have been performed.
Specification
- If the fault code is still active within the last 25 vehicle hours and all the preceding solution verifications have been performed, 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 EGR valve.
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.