Mercury - CAN Data Harness (10-Pin, No Resistors) 30-Foot SmartCraft Lead 84-879969T30. Overview. Big boats and long rigging channels often need far more cable than the standard SmartCraft lead provides. The Mercury 84-879969T30 CAN Data Harness adds thirty full feet of non-terminated SmartCraft wiring, giving you the room to route the harness cleanly through wide helms, deep consoles, and long structural runs. It carries CAN P, CAN X, and CAN H signals through the yellow 10-pin connector, makin