VALVE AR-ALT PATTERN CONTROL 3904341 - Caterpillar

Illustration 1 g02842516
Schematic of the CAN Data Link
This diagnostic code is recorded when the Transmission ECM is not sending the necessary parameters to the monitoring system at the proper rate. The update rate for parameters that are generated by the Transmission ECM is not correct. The communication failure may be due to disconnected connectors or a faulty wiring harness.The possible causes of this diagnostic code are listed below:
Software is installed on the Transmission ECM that is not correct.
Software is installed on the Brake ECM that is not correct.
Incompatible software may be installed.
The fuse for the Transmission ECM may have failed.
The fuse for the Brake ECM may have failed.Note: If the monitoring system is not operating correctly, refer to Systems Operation, KENR9023, "793F Off Highway Truck Vital Information Management System (VIMS)" for information on troubleshooting the monitoring system. Ensure that the diagnostic code is active before performing this procedure. Check the monitoring system for correct operation before performing this procedure. Test Step 1. CHECK THE TRANSMISSION ECM AND THE BRAKE ECM FOR PROPER SOFTWARE VERSIONS.
Use "Cat Electronic Technician (Cat ET)" to verify that the versions of software are compatible. Note: Consult your Caterpillar Dealer for the correct part numbers of the flash software.Expected Result:The proper versions of software are installed on the Transmission ECM and the Brake ECM.Results:
OK - The versions of software are compatible. Proceed to Test Step 2.
NOT OK - The proper software is not installed. Repair: Flash the proper software to the appropriate ECM. Cycle the keyswitch to initialize the new software. Ensure that the diagnostic code is no longer active.STOPTest Step 2. RECHECK FOR DIAGNOSTIC CODES.
Ensure that the diagnostic code is active. Expected Result:The diagnostic code is inactive. The diagnostic code indicator is inactive. Results:
OK - The diagnostic code is inactive. The diagnostic code indicator is inactive. Repair: Clear the diagnostic code. STOP
NOT OK - The diagnostic code is active. Repair: Ensure that the proper software is installed before replacing the ECM. If the software is correct, the Transmission ECM may have failed. A failure of the ECM is unlikely. Exit this procedure. Perform this procedure again. Prior to replacing an ECM, always contact the Technical Communicator your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM requires replacement, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".STOP