New navigation light won't power on

cranker789

My folding navigation light broke off so i got a new one. I've installed it fine but it's not turning on after connecting the wires. It gives a flash but doesn't power on when i hit the switch. The fuse looks good and there's at least some power going to the wires to the light. Any ideas what's going on? 
 

The Cat's Eye

There is résistance in the connection The flash is when the résistance reaches a point that it cuts off the current flow. 
Could be any of these:

Poor ground
Corrosion
lose connection
cold solder joint
defective bulb

etc.

gogittum

^^^^  Try connecting 12 vdc directly from battery to light.  That'll tell you if the unit is defective and give you a starting point.  Make sure polarity is correct....it makes a difference on some units.

cranker789

Just got my boat back from the boat yard and can’t figure it out. The bulb works connected it to another battery and it lit up. Checked the connections and there is nothing loose. May have to rewire everything. 

gogittum

cranker789 said:

Just got my boat back from the boat yard and can’t figure it out. The bulb works connected it to another battery and it lit up. Checked the connections and there is nothing loose. May have to rewire everything. 

????  Hmmm.....??  If it lights up connected directly to a battery, it has to be somewhere in the circuit on your boat.  Try disconnecting each terminal to see if there's anything preventing good contact - a bit of corrosion or a broken crimp terminal or such.  Is it a solid state light ??  Some (all ??) of them are polarity sensitive.  If an incandescent bulb, are the terminals shiny clean ??  (oh yah, it lights up on another battery.  Oh well)

It's quite rare, but I have seen where a wire has broken inside the insulation and the broken ends touching gave intermittent contact.  That will usually be pretty close to a connector.  Usually.

That was my problem on my Diesel Dodge on my 2003 Round-the-continent trip.  Fuel pressure started bouncing in GA, and it started cutting out in AL.  Dealer put in a new lift pump on warranty.  It quit cold near Carlsbad Caverns, NM and was towed into El Paso, TX.  Dealer there installed another lift pump.  Got back to Palm Springs, CA and it quit a block from home.  Dealer's mechanic there found that the wires in the lift pump connector were broken inside the insulation, right next to the plug.  New connector finally ended that.  Keep us posted.

Alex from GA

Becha it's an LED light and it's the wrong polarity.

cranker789

It is an LED light. The previous light was not LED. What do you mean by polarity? 

Alex from GA

An LED light doesn't work if the + and - wires aren't correct.  Switch them and see if it works.

gogittum

cranker789 said:

It is an LED light. The previous light was not LED. What do you mean by polarity? 

Mercy ! ! !   I mentioned polarity twice.  If it is/was a polarity problem, odds are good that the electronics are fried.  Try it.

cranker789

I thought that’s what polarity meant. Switched them and the same thing happened, a little flash. The wires coming from the battery are red and yellow and the wires from the light are black red so I was confused for a second but yellow and black go together correct? 

Gotsea

The polarity theory is correct, but you said you reversed the wires and nothing, that said, most electrical problem in a marine application can be trace to GROUND, the flash is a telltale of a ground that brakes with the load. 

The Cat's Eye

How old is your boat ?

If your boat was NOT originally wired with marine tinned copper the un-tinned copper under the insulation will start to turn black near connections that are exposed to the elements and creep along further along the wire. This corrosion adds resistance to the circuit and will eventually fail as it grows deeper into the copper strains of the wire.  To check for this condition you need to strip the insulation off at connections that are exposed to the elements. If the copper has turned black at any connection you should rewire that circuit. Eventually you will probably have to rewire the entire boat if it’s getting on in years. Re-wire with at least two different colors of marine wire.  

cranker789

little old boat. 1976 boston whaler 13. Its been modified from the original bw 13 look and all the wiring redone. The helm is raised for standing and the seat at the helm is a cooler seat with cushions. (bought it like this). This makes all the wiring hard to get too and see. I'll try and see if i can find the ground. 

cranker789

cranker789

The strange thing is the old anchor light was working before my brother used it as a handle. Now i get the new led one (which is too short and may have to be sent back anyway) and wire it up red w red, black w yellow, and vise versa and it doesn't work. It did work connected to another battery directly. 

The Cat's Eye

I 

Is your folding nav light the type that is inserted into a plug? If your light has this kind of connection I would remove the plug. Then after inspecting the wires for “Black corrosion” I would hard wire them to the light with connections that are designed for wet exposure.

 

CaptJ

Try a continuity test from the source to the end. That'll tell you pretty quick if it's a wire problem.

Klinger

Sounds like a bad ground. try running a temporary ground from the battery to the light. if it works,  replace the ground. might even be a broken wire inside the insulation as previously mentioned. sometimes a bulge in the wire where the wire has a pinhole exposing the copper to salt water 

cranker789

Thanks guys it’s the ground. Did like klinger said and did a temp ground to the stern eye and it’s lighting up. Will work on it later tonight when it’s dark but pretty sure it’s the ground wire

Gotsea

Glad you found it, ground is the first thing I look at when encounter an electrical problem, specially on a marine environment 

cranker789

Yeah ill keep that in mind... Still don't know why the ground isn't connecting but im gonna run a new ground wire tomorrow.  Hopefully have it running then. 

cranker789

Ok so it’s working thanks for saving me 200 at the mechanic fellas. Is there an easy way to get that wire through the tube into the fuse box? 

Klinger

If the old wire is still in the tube,  attach the loose end of the new wire to it and pull it through with the old wire 

cranker789

The old ground is attached the live wire which is still working in duplex wiring. So can't do that. Had to buy this stuff called fish tape, hoping that will do the trick. 

cranker789

All good now, fish tape got the wire through, light is working.

Gotsea

Excellent, hopefully you use the proper marine wire and connectors, Cheers go boating