Right marker light shorting out blinking on and off?

[Oasis Maker]

Well I've had an ongoing problem that I just knew for sure I fixed but it doesn't look that way. My right fender mounted marker light has always blinked. After experimenting, I assumed it was the ground wire the was built into the light fixture itself (no separate wire coming out).

So I just got a set of new marker lights and have the same problem. The new light has a separate exposed ground wire that is firmly bolted into the fender. But going over bumps, or even if I just tap the fender, it blinks on and off just like before. No other lamps are affected. I can only think the wire itself needs replaced because if it was a main ground problem with the trailer, everything would be blinking right?

Appreciate any help snuffing this out before I take off later this month. It's annoying me to no end.

Scott

[absolutsnwbrdr]

Sounds like a grounding issue between the fender and the trailer. Test it out by running a ground wire directly from the light to a grounding point directly on the trailer.

[Oasis Maker]

Sounds like a grounding issue between the fender and the trailer. Test it out by running a ground wire directly from the light to a grounding point directly on the trailer.

Thanks Zach, I'll give that a try. Jumping ahead, if I find that is the problem, should I bypass the fender and find a new grounding point on the trailer, or try and correct the issue at hand?

Scott

[absolutsnwbrdr]

If thats the problem, it'll probably be easier to just run a ground wire directly to the frame.

I had horrible grounding issues with my POS bolt-together HF frame

Ended up running a dedicated ground wire for the whole trailer.

[Oasis Maker]

If thats the problem, it'll probably be easier to just run a ground wire directly to the frame.

I had horrible grounding issues with my POS bolt-together HF frame

Ended up running a dedicated ground wire for the whole trailer.

Your response is the essence of K.I.S.S.

I'll give it a go over the weekend.
Thanks

[Steve_Cox]

I gave up long ago trying to keep a good ground through a trailer frame, fenders etc... The last 20 years or so, I've run ground wires to all trailer running/turn/brake lights. A little extra wire can simplify your life. Attachment of a ground wire to a side marker can be as simple as a ring terminal under the fixtures attaching bolt.

[madjack]

I gave up long ago trying to keep a good ground through a trailer frame, fenders etc... The last 20 years or so, I've run ground wires to all trailer running/turn/brake lights. A little extra wire can simplify your life. Attachment of a ground wire to a side marker can be as simple as a ring terminal under the fixtures attaching bolt.

...yup, me too also................................................................................

[Oasis Maker]

I gave up long ago trying to keep a good ground through a trailer frame, fenders etc... The last 20 years or so, I've run ground wires to all trailer running/turn/brake lights. A little extra wire can simplify your life. Attachment of a ground wire to a side marker can be as simple as a ring terminal under the fixtures attaching bolt.

Hey Steve, the new marker has a ring terminal and I really thought I would be golden because of it. When I saw it still shorting out, I thought about putting a washer in between it and the fender, but I think the problem is before that actual last connection.

Scott

[Oasis Maker]

I'm a little baffled though at everyone having problems with a ground even at the trailer frame? Wouldn't that be a slam dunk to just drill a little hole in that thick metal, bolt on and wallah??

Scott

[madjack]

I'm a little baffled though at everyone having problems with a ground even at the trailer frame? Wouldn't that be a slam dunk to just drill a little hole in that thick metal, bolt on and wallah??

Scott

Scott, you would think BUT, there is also the connection back to the tow and the additional problem of corrosion between two different types of metal and???????...well anyway, it presents some not unsolvable problems but a direct ground connection from the harness ground to a grounding block to all other grounds will usually eliminate these problems and give a common point to check if further problems occur........
madjack

[Oasis Maker]

I'm a little baffled though at everyone having problems with a ground even at the trailer frame? Wouldn't that be a slam dunk to just drill a little hole in that thick metal, bolt on and wallah??

Scott

Scott, you would think BUT, there is also the connection back to the tow and the additional problem of corrosion between two different types of metal and???????...well anyway, it presents some not unsolvable problems but a direct ground connection from the harness ground to a grounding block to all other grounds will usually eliminate these problems and give a common point to check if further problems occur........
madjack

Can anyone link me to some photos of a direct ground to grounding block or provide photos from your own build?

Slowcowboy, it sounds like you and I share the same headache. But it also sounds like you have some very cool marker lights... (teardrop marker lights?) You gotta show some pics of those - if only to provide me with a healthy does of buyers remorse.

Scott

[Oasis Maker]

You know MJ, the more I think about it, the more I'm inclined to do as you and Steve and.... etc. and just go with a direct ground because with the lights on, I never get a "clean" blink with my turn signals. Meaning, one side blinks while the other side dims a little. I don't know if this is an ahah moment or a duh moment.

I'm inclined to believe the latter.

Scott

[madjack]

...here are a few common types available from such as Radio Shack or the electrical section of box, hardware or auto part stores...it can also be as simple as gathering all of your grounds and soldering them together...on my TD, it is built such, that all the grounds are soldered directly into the harness................
madjack

[Larwyn]

I think it is probably those of us who have spent lots of time trouble shooting trailer lights that are most likely to simply run a dedicated ground wire to all of the lights. Bad grounds are almost always the cause of trailer light problems and when something else is the cause, the symptoms usually point directly at the problem. I used a fuse panel which incorporates a ground buss for the trailer's 12 volt system but for the trailer lights I just ran one wire for the ground and connected every light to that. It makes the difference between trouble free trailer lights and trouble shooting delays at hook up time. I learned this years ago on horse and stock trailers (a few boat trailers too) and some of them were so old that they had been built with only one tail/stop light.

I can remember a couple of times when we needed to move some horses at night that upon finding the tail light not working, my dad tied a red rag over the lens of a flashlight and wired it to the back of the trailer to get it home. I think this was probably more to protect the horse and trailer from other drivers than anything else and the lighting "problem" at the time was just a burned out bulb.

[bobhenry]

I think it is probably those of us who have spent lots of time trouble shooting trailer lights that are most likely to simply run a dedicated ground wire to all of the lights. Bad grounds are almost always the cause of trailer light problems .

2 1/2 years at U - Haul taught me to suspect the grounds first. At the first sign of a problem drag out the jumper cables and clamp one end on the tow vehicle frame and ground the other to the trailer frame. If problem persists extend the jumper cables with enough wire to reach the offending light and wrap a bared portion of the wire around the shank of a screwdriver and now touch the socket barrel around the light base.

NOTE : this is how I found the driverside taillight assembly ground on my H.F trailer does not connect to the metal as it should. A factory F.U. I guess!

If grounding with the screwdriver back to the tow vehicle does not work change the bulb.

Still nothing a test light grounded to your temporary wire and touch the positive terminals in the base of the socket will check for 12 volts. Be careful not to touch the grounded sides of the socket itsself.

I used a neutral bar designed for an electrical panel for my central ground.



It is the bare metal bar in the lower right.

I created 4 circuits right side ~ left side ~ cabin front ~ and galley

You can see the 4 fuses in the pic as well The round black item is a main fuse and manual disconnect I picked up at Advance auto parts.

EACH AND EVERY 12 volt item in the trailer has a dedicated ground they return on one of the 4 common legs to this grounding bar. There is a 10 gage ground wire attached to this bar that then returnes to the 4 way flat ground wire on the plug. I did take that 1 step further in that I spliced into this heavy ground another 10 gage wire that can continue on to the tow vehicle and be clamped onto a bare metal surface in the trunk or underneth on the tow vehicle frame.