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Our Winnebago EKKO has a “Whale Gulper” pump to drain the bathroom sink and shower.  It mostly runs on autopilot, but there are times when the autopilot makes the wrong decision about running the (rather loud) pump, so we wanted a way to shut this off with a switch.

But we also wanted that switch to light up when the pump was off (to remind us to turn it back on!).  But a Switch OFF/Light ON configuration requires a special kind of switch.  I show you what it is and how to install it in this video.

But this kind of switch could also come in handy in other situations, I explain that up front.  Have a watch:


I explain it pretty well in the video, but the switch I used here has a few key characteristics:

  • SPDT (Single pole, double throw), which means there’s one circuit that can be switched two different ways.
  • ON-ON, which means the switch is on either one way or the other.
  • NOT “ON-OFF-ON”  That would mean there was a center “off” position where neither path was energized.  We don’t want that.
  • NOT “ON-(ON)”.  The () would indicate a “momentary” switch, where the current path is connected only while you hold down the button.
  • Rated for 12 volts, 20 Amps, continuous duty.  That’s more than enough for the pump I wanted to switch.
  • Has an independent light circuit.  This means you can control the light independently of the switch position.


Materials List

The switch I wound up using was the V4D1-A60B from Carling industries.  I bought it from New Wire Marine.  (We have no affiliation with them at all.  They just had the switch in stock.)

But New Wire Marine sells the switch body bare.  I had to buy a cover plate for it to complete the switch.  I chose the “Bilge” lighted cover, which I also got from New Wire Marine.  (But they do have “custom cover” options – fun!)

I also got a mounting trim ring that just snapped into the bathroom cabinet without needing any screws or fasteners.  This is the one I purchased.

The fuse holder you see me installing is this one:  The Littelfuse 0FHA0030XP ACS ATO HD Carded Inline Fuse Holder.

I am using WAGO connectors to make the connections under the seat.  I think they’re super handy, and I’ve never had a failure related to one yet.  I use some 2-conductor connectors, and one 3-conductor connector.

I’ve really started to like this wire I’m using.  It’s this stuff, which I just got from Amazon.  It’s 14 gauge, so it can handle 15 amps.  It comes in various colors, which make identifying wires in the bundle easier.  The copper strands themselves are tinned to help resist corrosion.  But most importantly, the silicone insulation on the wire is super flexible.  It makes it very easy to work with and it will bend and move wherever you want it.

If you’re looking for some super-flexible wire loom to go with the super-flexible wires, you could try this Alex Tech Cord Protector.  The only bad thing I can think to say about it is that you have to singe the ends of the tubing where you cut it so that it doesn’t unravel.

Finally, the wire strippers that you see that sometimes work fantastically and sometimes just try to frustrate me are these Irwin wire strippers.  They work great on the silicone insulation, but struggle with firmer insulation.  I suppose this just means they’re out of adjustment somehow, and I should just figure out how to adjust them.


As I mentioned in the video, this “warning light” function isn’t the only time knowing a switch like this would come in handy.  It would also make a perfect night-light or locator switch in your RV.

Anyways, the rest of the information you need to get this working is in the video.  If you have comments or questions, sound off below and I’ll try to answer them for you.