Nav/Anchor light "3 way" switch wiring help!

DunbarLtd

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Nov 8, 2016
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I was wondering why there are 6 wires going into a SPDT 20Amp toggle switch. It is ON-OFF-ON.

It has only 3 terminals. And 2 wires going to each terminal via some type of blade coupling.

Why not just use a 6 blade terminal switch? I dont understand the wiring for this. Anyone have any ideas how this is supposed to work and why someone chose to use a 3 terminal switch vs 6 terminal?

Heres a switch just like the one I have. Its made by Carling. But I cant find any number on it. I believe it is a "D" series but not sure.

https://www.zoro.com/nsi-industries-toggle-switch-bat-spdt-on-off-on-78070tq/i/G1630157/
 

alldodge

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It may not be wired correctly
Which lights turn ON/OFF as the switch is moved?
 

DunbarLtd

Petty Officer 1st Class
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Nov 8, 2016
Messages
335
It may not be wired correctly
Which lights turn ON/OFF as the switch is moved?

On the switch UP is NAV and DOWN is ANCHOR. Middle position is OFF.

We are getting power with test light to a pair of the wires that were connected to the switch but no power at either light. Fuses and bulbs check out. Im just trying to figure out how to wire it so we can rule that out as the problem. The original switch was snapped off (cheap plastic), so we bought a new one and are trying to figure out how to wire it properly.

Im assuming one side of the switch turns both lights on and the other side only turns on maybe the anchor light. Wouldnt make sense to have ON OFF ON and not be able to turn both of them on. The lettering on the panel is faded and i cant read it. Looks like nav and anchor though.

And how this is accomplished with only a 3 terminal switch is confusing. Never seen this before. Usually see 6 terminal switches for this application. We did notice a YELLOW tubular thing encapsulating a couple wires coming off the switch. Maybe a diode?? im not sure?

Its an old late 80s Four Winns 180 I believe (4.3 OMC) with the fuses sticking out of the console panel. No fuse block that I can tell. Buddy just bought it and we are trying to figure it out.
 
Last edited:

GA_Boater

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Stickies have a lot of answers to questions - https://forums.iboats.com/forum/boat...5#post10803725

For a SPDT to work, a diode is required.

When you flip the switch, is one switch side dropping power? That would the the bow light. The other side should have power from the switch except the mid-position. Check continuity from the switch to the light sockets.

All your why questions - Only your hairdresser knows. We don't know why.
 

alldodge

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Need power on the center contact and diode as GA mentioned. I would change the switch out for a 6 pin DPDT switch and make it easier. Find which has power and start there. Then connect the other wires one at a time to the one which has power so you know which lights what bulb.

fetch
 

tblshur

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Aug 24, 2011
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Diode blocks current flow to Navy light When stern light is on Hope I got that right anymore I am under impression both nav and sturn have to be on in all low light conditions:eek:
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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both the all-around light and the front bi-color light must be on when under-way at night

the all-around light must be on when you are anchored.
 

jhebert

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Jul 24, 2005
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902
Generally with modern switches with some sort of illumination built into the switch, it is common to see many conductors wired to the switch. The circuits are generally:

--12-Volt positive power
--load of a lamp or lamps circuit
--load of a second circuit for lamp or lamps
--an illumination lamp ground return to complete the circuit for the internal lamp
--jumpers of 12-Volt power or lamp ground to other adjacent switches.

A detailed drawing shown the wiring and switch action for a modern rocker switch controlling navigation lamp lighting circuits can be seen and explained in detail at

http://continuouswave.com/forum/view...p=23400#p23400

The switch action can also be very complicated. And the wiring can be quite non-intuitive.
 
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