Mercury – Harness Extension (Triple/Quad/5/6 Engine) | 48-Inch Multi-Engine Extension | 84-8M0158127

Overview
This 48-inch extension gives you extra room to run trim wiring on larger multi-engine setups—triple, quad, and even 5- or 6-engine rigs. It includes the dash lead, the ERC pad lead, and the Y-harness, so everything plugs in cleanly without piecing parts together. If you’re running Zero Effort controls or the bigger multi-engine dash trim pads, this extension helps the wiring fall into a smoother, more natural route.

Key Features
    • 48-Inch Extension – Adds length for longer runs in big multi-engine boats.
    • Dash + ERC Pad Leads – Includes both connection paths in one setup.
    • Y-Harness Included – Splits the circuit cleanly for multi-engine trim pads.
    • Zero Effort Compatible – Works with ZE control setups.
    • OEM Connectors – Factory plugs that snap in tight and stay put.

Engine & Boat Compatibility
    • Triple engine
    • Quad engine
    • Five-engine rigs
    • Six-engine rigs
    • Zero Effort controls
    • Multi-engine dash trim pads

Performance & Practical Benefits
A bit of extra harness length makes a big difference on wide or long-deck boats. The wiring can follow a relaxed path instead of getting squeezed behind panels or forced around tight corners. That usually means cleaner trim response and far fewer issues down the road. It also keeps the rigging bay from turning into a tangle, which makes life a lot easier during service.

Why Buy OEM
OEM extensions fit the connectors exactly the way Mercury designed them. They hold up to vibration, spray, and heat, and you don’t get the loose-fit headaches or random trim glitches that come with off-brand extensions.

FAQ
Q1: When would I need this extension?
A: When your trim pad or Zero Effort wiring won’t quite reach across a triple, quad, or 5/6-engine layout.

Q2: Any setup or calibration needed?
A: None—plug it in and it works right away.

Q3: Saltwater friendly?
A: Yes. Just rinse and check the connectors from time to time.

Q4: Any installation tips?
A: Give the harness a smooth route with gentle bends so nothing gets pulled tight.

Q5: What are early signs of wear?
A: Uneven trim response, intermittent behavior, or jacket rubbing along tight spots.