Mercury - Ignition Harness Non-DTS 14-Pin Engine Ignition and Gauge Wiring 84-896537T15. The Mercury Non-DTS Ignition Harness is designed for mechanical control setups that require additional reach between the helm and the engine without moving to an oversized harness. Its 15-foot length makes it a practical option for boats with forward-mounted helms, while still keeping wiring runs clean and manageable. This harness helps maintain an orderly ignition and gauge wiring layout without tension or