SAE J1587

The J1587 protocol is a diagnostic protocol for automotive engineering developed by the Society of Automotive Engineers( SAE) for trucks, buses and heavy-duty vehicles.

The J1587 protocol is intended to ensure consistency in the software used in the various electronic control units(ECUs). The J1587 protocol is most often used in conjunction with the J1709 protocol, which is used to describe hardware and general communications. The combination of both protocols provides cost savings in the development of microcontrollers for trucks and buses.

The J1587 protocol is used for data exchange between electronic control units in trucks, for driver information, maintenance and diagnostics. Driver information is about the data for the digital tachograph and the trip logbook, furthermore it is about navigation and time data, loading and unloading points and times. As for the diagnostic functions, these are accessed via multi- pin connectors. There are various diagnostic plugs, a 6-pin one that was used between 1996 and 2001 and was subsequently converted into a 9-pin diagnostic plug.