TROUBLESHOOTING SHACK

*Important Note-Before starting the diagnosis process, verify that the ECM calibration is up to date. An outdated ECM calibration can lead to issues with sensors and modules.

Cummins Fault Code: 6255 SPN: 1569 Engine Protection Torque Derate – Data Valid But Above Normal Operating Range – Least Severe Level

Cummins Fault Code: 6254 SPN: 5246 Aftertreatment SCR Operator Inducement Severity – Data Valid But Above Normal Operating Range – Moderately Severe Level

Code Analysis:

When these fault codes appear, it indicates that the engine is experiencing a derated state. Serving as “information only” alerts, these codes inform us that the engine has enacted protective measures due to an existing issue requiring resolution.

Troubleshooting Steps:

Check for Related Active Codes:

Before addressing codes 6255 and 6254, it is essential to check whether other active codes relate to the aftertreatment system (DEF system, DEF Dosing, NOx, SCR), intake, or turbo. Addressing any additional codes should take precedence before attempting to resolve codes 6255 and 6254.

Verify ECM Calibration Version:

Once all necessary repairs are complete, and codes 6255 and/or 6254 persist, it’s important to ensure that the ECM calibration version is up-to-date. Promptly updating the ECM, if outdated, is crucial.

Test Drive to Identify Unresolved Issues:

With an updated ECM, conducting a test drive is recommended. The aim is to potentially trigger any additional fault codes connected to underlying issues contributing to the persistence of the information-only codes.

Calibrating the ECM as a Last Resort:

In rare scenarios where no additional codes are triggered after the test drive, technicians may contemplate calibrating the ECM with its current version as a last resort. However, caution should prevail, as this approach bears inherent risks. Calibration failure could result in rendering the ECM inoperable.

To effectively troubleshoot Cummins fault codes 6255 and 6254, adhering to a systematic approach is paramount, which includes addressing related active codes and ensuring the ECM’s up-to-date status.