Blue Sea 4180 Backlit Push Button Switch OFF/ON - 15A

Blue Sea Systems builds electrical gear that survives the wet, pounding, corrosive life aboard a boat, and the 4180 push button switch is a small part that quietly does its job for years. It's a 15-amp OFF-ON switch with a backlit button that glows blue when the circuit is off and red when it's on. So one glance at the helm tells you what's running, day or night. No guessing whether the anchor light is still on. The button color does the talking.

This is a latching switch, not a momentary one. Push it once and the circuit stays on. Push it again and it's off. That makes it right for the loads you leave running: bilge pumps, anchor and running lights, cabin and courtesy lighting, accessory circuits, wipers, and horns. Blue Sea includes five ICON labels in the box (Accessory, Lights, Anchor Light, Running Light, and Bilge Pump) so the switch reads clearly on the panel. If none of those fit your circuit, the 50-label ICON kit is sold separately and covers just about everything on a typical dash.

The color-change backlight is the feature that earns its keep. On a night run, a panel of identical black switches is a guessing game. With the 4180, off reads blue and on reads red across the whole panel, so you can confirm your running lights, bilge, and electronics at a glance without reaching for a flashlight. It's a small thing that makes a dark helm a lot less stressful.

The 4180 drops into a standard 7/8 inch (22mm) mounting hole and works on panels up to 0.24 inch (6.1mm) thick. That covers most fiberglass and aluminum helm panels. On a thick console you might want a backing plate or a shallow bezel to close the gap, something we've had to do on a few center consoles with heavy layups. Termination is a 3 inch bare-wire pigtail, so you're crimping or soldering your own connectors to match your harness. The load wires are 14 AWG (red and red/white) and the backlight wires are 18 AWG (black and blue), which tells you how to size your runs.

Here's the honest part on capacity. The switch is rated 15A at 12V DC, with a 15V maximum. That's plenty for lights, most accessories, and small pumps. But a big bilge pump, a windlass, or a high-draw motor can pull well over 15 amps on startup, and this switch isn't the right tool to carry that load directly. On those circuits, wire the switch to a relay or solenoid and let the heavy contactor do the work. Always protect the circuit with a properly sized fuse or breaker. It pairs cleanly with a Blue Sea fuse block like the 5025 when you're wiring a single-switch circuit.

A few install tips from the dock. The backlight LED needs its own 12V feed and draws only 20mA, so a lot of folks tie it to the nav light circuit so it lights up whenever they're running. Give the ground wire a good common connection with your other Blue Sea switches so the backlight doesn't flicker. And a dab of dielectric grease on the terminals goes a long way against salt spray, especially on an open boat. Do that and the switch shrugs off salt air for a long time.

Blue Sea rates the mechanism for 10,000 switching cycles and an operating range of -20 to 55 degrees C, so it holds up from a cold spring launch to a hot August afternoon. For a switch you'll reach for a few times every trip, that reliability is what you're really paying for. It's a clean, readable, well-built OFF-ON control that looks right at home on any Blue Sea panel.