Mercury - Diesel Vessel Sensor Harness Sterndrive Sensor Wiring Harness 84-8M0118368. The Mercury Diesel Vessel Sensor Harness is designed for diesel sterndrive applications where additional vessel sensors must communicate reliably with the engine system. It serves as a centralized wiring solution, allowing optional sensors to integrate cleanly without compromising signal quality or overall system stability.. This harness supports both DTS and non-DTS diesel sterndrive setups, including Axius-eq