Definition of Standalone Mode
Standalone mode is defined as when the PLC/J1708 Adapter is not physically connected to a PC.

Standalone Tractor and Trailer Modes
The PLC/J1708 Adapter operates in two different standalone modes based upon pin 4 of the DB15 connector.

• Tractor Mode - (DB15 pin 4 floating) - In this mode, the adapter simulates a tractor and listens to the PLC bus. It lights both the internal "ABS Lamp" LED and external ABS lamp (if connected) if an ABS fault message is seen.
• Trailer Mode - (DB15 pin 4 grounded) - In this mode, the adapter simulates a trailer ABS unit and sends PLC messages that will cause the in-cab tractor ABS lamp to cycle off and on at a 5-second interval.

Standalone Gateway Mode
When in "standalone" mode, the PLC/J1708 Adapter "gateways" all traffic found on the PLC bus (DB15 pins 6 and 8) to the J1708 bus (DB15 pins 14 and 15) and vice versa. Note that both the PLC and J1708 LED's will flash.

Pinouts and Functional Descriptions
The following describes the pinouts necessary to create a cable using a DB15 male connector.

Sample Wiring Diagram
Below is an example of a wiring diagram that has switches for power and selection of Tractor/Trailer mode as well as showing how to connect an external 12-volt ABS lamp.