How to Install the MG250W.64 Marine In-Dash Receiver

By BOSS Audio Systems | Life at Full Volume | Published: 2026-10-27

Category: How-to Guides

Step-by-step guide to installing the BOSS MG250W.64 marine in-dash receiver, including wiring, mounting, and common mistakes to avoid.

Quick answer

Installing the MG250W.64 marine in-dash receiver is a straightforward DIY project if you plan the wiring and mounting carefully. Follow the steps below to get it done safely and avoid common pitfalls.

Why the MG250W.64 is built for marine use

The MG250W.64 is designed to withstand the harsh marine environment, with an IPX6 rating that protects against water jets and dust. Its conformal coated PCB adds extra protection against corrosion, making it a reliable choice for boats and other outdoor vehicles.

Before you start, gather the necessary tools: wire strippers, crimpers, electrical tape, heat shrink tubing, a drill with appropriate bits, and a marine-grade wiring kit. Having everything on hand will make the installation smoother.

Step-by-step installation guide

Disconnect the battery: Always disconnect the negative battery terminal before working on any electrical component to prevent shorts or damage. Double-check that the battery is disconnected before proceeding.
Remove the old unit (if any): Use a removal tool to slide out the existing stereo. Disconnect all wiring harnesses and antenna cables carefully. Label each wire or take a photo for reference during reconnection.
Prepare the wiring harness: Connect the MG250W.64's wiring harness to your boat's existing wires. Match colors: red to ignition, yellow to constant power, black to ground, and pair the speaker wires by color. Use crimp connectors or solder and heat shrink for reliable connections. Ensure all connections are secure and insulated to prevent shorts.
Mount the receiver: Slide the MG250W.64 into the dash opening. The cutout diameter is 3 inches (76 mm), so verify your dash opening matches. Use the provided mounting sleeve and secure with the included screws. Check that the receiver sits flush and does not obstruct any controls or vents.
Reconnect the battery and test: Reconnect the negative battery terminal. Turn on the receiver to test all functions: AM/FM, Bluetooth, USB, and speaker output. Ensure the illuminated controls light up correctly. If the unit does not power on, check the fuse and wiring connections.

Key features of the MG250W.64

MG250W.64: IPX6-rated weather-resistant and dustproof construction with a conformal coated PCB. This protects the receiver from water splashes and corrosion, so it can handle marine conditions without failing prematurely.
MG250W.64