FENDER-REAR 3949508 - Caterpillar

Illustration 1 g00678674
Schematic of the SPI data link
This diagnostic code is recorded when the VIMS ECM is not sending the necessary parameters to the speedometer/tachometer module at the proper rate. The update rate for parameters that are generated by the VIMS 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:
The VIMS ECM is installed with a software that is incorrect.
The speedometer/tachometer module is installed with a software that is incorrect.
Incompatible software may be installed.
The fuse for the VIMS ECM may have failed.Test Step 1. CHECK THE VIMS ECM AND THE SPEEDOMETER/TACHOMETER MODULE FOR PROPER SOFTWARE VERSIONS.
Use Caterpillar Electronic Technician (ET) in order to verify that the versions of software are compatible. Expected Result:The proper versions of software are installed on the speedometer/tachometer module and the VIMS ECM.Results:
YES - The versions of software are compatible. Proceed to Test Step 2.
NO - The proper software is not installed.Repair: Flash the proper software to the appropriate ECM. Cycle the key start switch in order 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 Ensure that the diagnostic code is no longer active.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:
YES - The diagnostic code indicator and the diagnostic code are inactive.Repair: Clear the diagnostic code.STOP
NO - The diagnostic code is active.Repair: Ensure that the proper software is installed before replacing the ECM. If the software is correct, replace the speedometer/tachometer module. If the speedometer/tachometer module was just replaced , install a new VIMS ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace" for the machine that is being serviced.STOP