ENGINE AR 3852786 - Caterpillar

Table 1
Troubleshooting the Harness Code    
Connector and Contact    37    38    39    40    
Interface Module (MID 57)     grounded     grounded     grounded     open    Note: The harness code is similar to the personality module identification code. Both terms are used to describe the particular interface module that is sending information to the VIMS main module. The harness code is the status (open or ground) of the harness code inputs. The module identifier is the number that is assigned to a particular harness code for a particular electronic control module. Each module has a specific harness code. Therefore, each module also has a specific module identifier. The correct harness code is given in the Electrical System Schematic. This failure is recorded when the circuits of the harness code change during normal operation. In order to perform this procedure, the specified harness code for the module must be known. The "Harness Code Troubleshooting" table above lists the specified harness code for the interface module. Test Step 1. CHECK THE HARNESS CODE.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness from the interface module.
At the machine harness connector for the VIMS module, check for continuity between the contacts of the harness code connector and contact 2 (ground). The machine's Electrical System Schematic or the table for Troubleshooting the Harness Code should be used in order to determine the configuration of the contacts for the harness code. The contacts are grounded or the contacts are open.Expected Result:The harness code is correct.Results:
OK - The harness code is correct. No defect was found in the circuits of the harness code. Reconnect the harness connectors. The problem is intermittent or the module may have failed. Stop.
NOT OK - The harness code is not correct.Repair: Repair the harness code circuits or replace the harness. Stop.