Mercury – MP Alert Harness Extension | 10-Foot Forward Routing Cable | 84-8M0054183
Mercury – MP Alert Harness Extension | 10-Foot Forward Routing Cable | 84-8M0054183
Mercury – MP Alert Harness Extension | 10-Foot Forward Routing Cable | 84-8M0054183 is backordered and will ship as soon as it is back in stock.
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Description
Description
Mercury – MP Alert Harness Extension | 10-Foot Forward Routing Cable | 84-8M0054183
Overview
Some MP Alert installations require a forward-mounted light—especially on boats where swimmers or riders might approach from the bow or forward quarters. The Mercury 84-8M0054183 MP Alert Harness Extension gives you a clean, 10-foot extension to route an MP Alert light toward the front of the boat. It plugs directly into the existing MP Alert wiring and keeps the system’s warnings visible well beyond the transom.
Key Features
- 10-Foot Extension Harness – Adds extra length for mounting an MP Alert light toward the bow or forward deck.
- Plug-and-Play Fit – Connects directly to the existing MP Alert harness with OEM SmartCraft-grade connectors.
- Supports Safety Coverage – Helps position lights where they’re easier for swimmers and passengers to see.
- Flexible Routing – Long enough to run through consoles, side panels, or bow passageways.
- OEM Marine Build – Weather-sealed cable designed to handle vibration, spray, and temperature changes.
Compatibility
- MP Alert systems (all oval-light versions)
- SmartCraft-compatible engines
- Additional or relocated MP Alert lights
- Boats needing forward-facing Moving Prop warnings
Performance & Practical Benefits
This harness lets you extend your safety zone by adding or relocating a Moving Prop Alert light to the front of the boat. The extra 10 feet give you room to route the cable cleanly through bulkheads and rigging channels, keeping your wiring neat and protected. Once connected, the forward light activates automatically with the rest of the MP Alert system, flashing whenever the prop is turning so people approaching from the bow can clearly see the warning.
Why Buy OEM
The MP Alert system depends on reliable signaling and solid, sealed connectors. Mercury’s OEM extension harness fits correctly, keeps moisture out, and preserves the timing and brightness of the warning lights. Aftermarket extensions often introduce weak connections or intermittent behavior, but the factory harness keeps the system consistent and trustworthy.
FAQ
Q1: When would I need this extension harness?
When mounting an MP Alert light toward the front of the boat or when the standard harness is too short for your layout.
Q2: Does installing this change how the system works?
No. It simply extends the wiring—activation remains fully automatic.
Q3: Is it compatible with all MP Alert kits?
Yes. It works with any Mercury MP Alert system using oval smart lights.
Q4: Does this require a Y-harness?
Only if you’re adding an extra light. For relocating a light forward, this extension is all you need.
Q5: Is the cable marine-rated?
Yes. It’s fully sealed and designed for long-term marine exposure.

