J1939 Type 2 to Type 1/2 Jam Nut Y Cable The full parameter set is

The full parameter set is overwhelming for all but professional tuning applications

The connectors are wired differently and it is possible to damage your equipment

One of the most common is to view the data iin tabular form such as the screen capture below

ECM555 0401

6 contacts are Y'ed through to the two vehicle side connectors:

J1939 Type 2 to Type 1/2 Jam Nut Y Cable The full parameter set isY cable for J1939 Type 2 systems. This cable includes one Type 2 Female (sockets) connector to plug into your vehicle connected to one Type 2 Male (pins) bulkhead connector and one Type 1 Male (pins) bulkhead connector. This allows you to plug one Type 1 accessory and one Type 2 accessory into one vehicle bulkhead connector. The 9 contacts are wired as follows: Signal Name Type 2 F Type 2 M Type 1 M Ground A A A Battery B B B J1939 Type 2 High C C C