It is a tool that displays basic J1939 component information and J1939 voltage that can help trace J1939 malfunctions in the Cummins proprietary data link to a particular location in the harness and down to the exact wire.
Then refer to the Analyzing the Data section in the service procedure. It contains 5 scenarios that are often experienced in the field and can be diagnosed easier by using the J1939 Data Link Diagnostic Tool. All of these sections help fault isolate efficiently and get the end user to the root cause of the data link issue. To understand which scenario is being dealt with currently, collect the average values of the J1939 voltage and busload located in the J1939 Data Link Diagnostic Tool Component Status and CAN Voltage tab. Then, proceed to the matrix that guides to the right section of the procedure to begin troubleshooting.