REAR STRUCTURE 8T3388 - Caterpillar

Which Generate This Code:This diagnostic code is associated with the Modulating Valve (No. 6) for Speed Clutch 1. The FMI 13 means that the ECM has determined that the modulating valve needs calibration. Once the calibration for the modulating valve " Speed Clutch 1" has been performed successfully, this diagnostic code will disappear. This failure is active on a new ECM.Possible causes of this diagnostic code are listed below:
The solenoid has failed.
The ECM has been replaced or new software has been installed.
The ECM has failed.System Response:The machine response is listed below:
Shifting may be harsh or sluggish.Note: Ensure that you have repaired any condition that would cause other active diagnostic codes that are related to this solenoid. For example, the CID 1406 FMI 03 or FMI 05 are not active when the CID 1406 FMI 13 is active. If the other diagnostic codes are active, troubleshoot those codes first. Then perform this procedure.Note: Ensure that the diagnostic code of CID 1406 FMI 13 is active before performing this procedure.Test Step 1. CHECK THE CALIBRATION
Perform the calibration procedure. Refer to the Testing and Adjusting section of the Service Manual for the correct procedure.
Observe the status of the CID 1406 FMI 13.Expected Result:The CID 1406 FMI 13 is active.Results:
YES - The CID 1406 FMI 13 is active. The diagnostic code has not been corrected. Verify that the correct software has been flashed into the ECM, or that the correct ECM is installed on the machine. Then repeat the calibration.Repair: If the diagnostic code is still active and the cause of the diagnostic code is not found replace the ECM. It is unlikely that the ECM has failed. Verify that the solenoid and associated circuits are correct before you replace the ECM.STOP
NO - The CID 1406 FMI 13 is not active. The calibration corrected the condition that caused the diagnostic code. Repair: Resume normal operation.STOP