Neither of my running lights are working. I hop over to Sky Guys house, barrow his multimeter and find I have a solid 12 volts inside the fixture. So I run out and buy new bulbs. Still no light. How the hell can I have 12 volts inside the light fixture and not have my lights work? Any ideas?

bad ground?

Use the ground for the lamp inside the fixture for your test. Corrosion is the enemy.

those perko ones? i had nothing but trouble with mine. ended up buying a flashlight type one that clamps to the bow as a backup. when you say "inside the fixture" do you mean right before the bulb? you can take the point of the probe and poke it through the insulation just below the bulb . it could be the contact in the hull, or the bulb socket. check for corrosion, clean and apply dielectric grease. good luck



willy

Yeah, the Perko ones.

By inside the fixture I mean that I touch the probes to the contacts inside the fixture. I have cleaned the contacts and sprayed WD 40. Nada. Treis severl bulbs in hopes one was bad. Nada.

Sky Guy, if you wnat your multimeter back better come over see if you can help figure out the problem.

Maybe I too will just buy the flashlight clam on ones. My boat is just a 16 foot Smokercraft and I damn seldom run after dark. Maybe I need a new Alumaweld.

yeah but if you're grounding the multimeter to something other than the ground the light fixture is using, the test won't tell you if the fixture's ground is bad....

LD is on it.

LD: This is not my strong point, but if I'm touching the probe to the two contact points inside the fixture and I get a reading of 12 V doesn't that mean the fixture's ground is good?

Not if you have a seperate wire (other than the probe) coming off the multimeter to a seperate ground..... Do you recall if that's the case or not? On my tester I have an aligator clip that goes to a ground (in my case I ran a long lead to it so I could reach anywhere in the boat from my neg terminal on my battery,) and then the pointed probe that can be pushed through wires to trace the charge. So if my probe showed a reading at a fixture, for instance, but I couldn't get the light to work even with a new bulb, by process of elimination it must be a bad ground.

I'm not familiar with the Perko fixtures... If you can trace the wires leading out of the fixture, examine the contact point for the black one, and if possible use it for the ground wire on your multimeter.

What a pain, this is something that would take 5 seconds to demonstrate in person, but it reads like stereo instructions on here.

No my multimeter does not have a seperate clip that goes to ground. Just a balck and a red.

Screw this. I will take it into Three River and let them sort it out.

Thanks for the help. I do preciate it.

An electrical engineer you ain't.

No argument Sol!

Dave, your problem is simple. I am willing to bet that everything is grounded to the boat....Bad idea. Every manufacture does it, and they should be shot for it.

Corosion and bad grounds is your problem. The boat needs rewired, it just takes some time.

Be happy to do it for you if you want to drive south with it.

You're not alone. When I wired up the 24 volt system in my drift boat for my trolling motor I fuc%ed up and crossed terminals and melted the insulation off every inch of about 12 feet of expensive battery cable in two tenths of a second. Filled the garage with toxic plastic smoke, etc.

I fuggin' hate trizity.

the perko socket (ala smokercraft--i have the same) has 2 ridgid pins in the bottom of the socket. the contacts in the post (where the bulb is) are just little springs, designed to contract inside the post. the problem is that there's not a lot of positive contact surface area. you can try and clean the springs, and scuff up the pins to get better contact. check the bulb socket while the post is in the socket. if you don't have your 12Vdc there, it's the connection in the socket.


willy

My running lights went out in my boat. I fixed it by replacing the fuse. I'm not sure if you have a fuse box on your boat. Maybe they have an inline fuse in the wire. Cheap item to replace for me. Good thing I'm putting my Chemical Engineering degree to work. Ha Ha!

Cant be a fuse if he sees 12V at the outlet. Putting my EE deg to work...

My bet? Two burned out bulbs. The old one AND the new one. If I'm reading your description right, you have 12v across the two points the lights touch, that seems the most likely explanation.

I gone through this many times with the Perko lights, it is always corrosion. Even if you measure 12 volts, a corroded connection will drop the voltage under load. Just last week I hope I solved the problem permanently, buy LED sealed lights. They are not that expensive, use less power and are brighter. They should last forever unless they are mechanically damaged. My only problem was that I unhooked the trailer while I was getting parts and when I returned I had a $38 ticket for leaving a detached trailer on the street.

Dave I could swing over tomorrow and take a look. I have some free time and the good lord knows I've spent plenty of time between my two boats working on "those damned trailer lights."

Call me if you havent already settled on taking the rig to 3R.

it is always corrosion I would clean the terminals/contacts where the bulb meets the source. If there is some kind of spring involved make sure it still works. Sometimes the spring has lost the ability to create presure on the terminals.

Try something like steelwool, emery cloth or sandpaper on the terminls where the bulb contacts the fixture.

Thanks guys. I think I will let Sky Guy come by and try to help me figure it out. I am sure the issue in the rear light is corrosion, as I do have 12 V at the contacts inside the fixture. The front may be yet another issue.

I KNOW I will regret saying this, but at least my tralier lights work well.

Now yer FUC%ED!

Yup, cursed you are.

Dave, Did you check at the bulb or the contacts of the fixture? A reading at the bulb would indicate an open in the circuit (bad contact or bad at the bulb.)

I have to fix a bad running light on my trailer. The wire looks to be fried. The copper is black between the wire and the insulation. Might have to rewire it. The wire was loose were it corroded away from the connector.

Dave, 12 volts is available. Thats not the same as CURRENT.

Once the current passes thru the light bulb, the 12 volts is gone. If the light is bad or has a bad connection, you can run a test light or volt meter with the red on the hot side of the bulb and black touching the cold side wire. Dont touch ground directly with the black or it will register positive.
The hot lead into the volt meter or test light will register 12 volts if you touch ground.

Do touch those two areas and it will tell you if the ground is good.
You can also switch to OHMS and measure the resistance ONLY with no power going to the circuit. Touch the wire down stream of the bulb and touch the end of the ground wire or touch the frame. You should get a beep. (test it before and touch the two leads together while set on OHMS) You should get almost identicle result. If not you have resistance or the open in the wire.

corrosion causes resistance. In the electrical equation, resistance is going to reduce voltage going to the light and it will not light up. Two bulbs can accomplish the same thing, but in most cases the two bulbs will be dim and yet the voltage will be used up, by the time it gets to the ground.