I have a set of 4 wire LEDs on a motorcycle trailer I'm having a heck of a time keeping working. About once a month or so I start having problems with the lights either not working at all, or lighting very dimly. Usually the problem is caused by a poor ground, but this morning I cleaned the grounds and the lights are still very dim, so I guess I'll have to replace the whole light set, AGAIN! Is it normal to have problems this often with trailer lights, or am I doing something wrong? This is ridiculous!
Trailer lights
- Thread starter grampi
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Run some short wires from the lights directly to a battery. If the lights are still dim, they're bad. If they light up bright, there's a wiring problem.
I briefly considered LED lighting for my 5x8 utility trailer when I re-wired the whole thing, but given the amount of trouble that some people have had with them, and given that you have to replace the whole LED unit if you do have issues, I elected to use standard incandescent lights.
Do you have a set of conventional lights you can wire-in and test? Or, can you take the lights off and wire them direct to a 12v car battery to see if they light bright? If they're inexpensive off-shore LED light kits, the voltage drivers in the lights themselves may be flaky.
Do you have a set of conventional lights you can wire-in and test? Or, can you take the lights off and wire them direct to a 12v car battery to see if they light bright? If they're inexpensive off-shore LED light kits, the voltage drivers in the lights themselves may be flaky.
I have the LED lights, and overall I like them. But I ran a discrete ground wire to each one rather than relying on the chassis. So far that has been over 10 years ago and they still work great. You might consider that.
Also using those heat-sealed crimp connectors helps a lot to keep moisture out of the connections.
Also using those heat-sealed crimp connectors helps a lot to keep moisture out of the connections.
Around 10 years back, I replaced it all on my trailer, and did it my way.
I replaced all of the wiring, all of the lights, the plug... I connected my own grounds... everything.
That was what it took to finally make the lights reliable.
I replaced all of the wiring, all of the lights, the plug... I connected my own grounds... everything.
That was what it took to finally make the lights reliable.
Something about LEDs and their tiny current draw means they need computer-grade connections. Incandescents seem to draw enough to "blast through" a little oxidation.
How do you do turn signals and brake? Do you have three bulbs on the bike that go through a "smart box" to make two bulbs on the trailer?
How do you do turn signals and brake? Do you have three bulbs on the bike that go through a "smart box" to make two bulbs on the trailer?
Originally Posted By: eljefino
Something about LEDs and their tiny current draw means they need computer-grade connections. Incandescents seem to draw enough to "blast through" a little oxidation.
How do you do turn signals and brake? Do you have three bulbs on the bike that go through a "smart box" to make two bulbs on the trailer?
Sorry, this is a motorcycle trailer that I use to haul my bike ON, it's not one that I tow with my bike...
Something about LEDs and their tiny current draw means they need computer-grade connections. Incandescents seem to draw enough to "blast through" a little oxidation.
How do you do turn signals and brake? Do you have three bulbs on the bike that go through a "smart box" to make two bulbs on the trailer?
Sorry, this is a motorcycle trailer that I use to haul my bike ON, it's not one that I tow with my bike...
Originally Posted By: eljefino
Oh, but my point stands, do you have amber turn signals and a box to make it work?
Not quite sure what you're asking...all of the lighting kits I've had for this trailer are the 4 wire type and they come with a plug that splices into the car's tail light wiring...the car's tail lights are the factory ones and the trailer lights are LEDs, don't know of any box...
Oh, but my point stands, do you have amber turn signals and a box to make it work?
Not quite sure what you're asking...all of the lighting kits I've had for this trailer are the 4 wire type and they come with a plug that splices into the car's tail light wiring...the car's tail lights are the factory ones and the trailer lights are LEDs, don't know of any box...
If your tow vehicle has seperate amber bulbs for the turn signals, there's a small diode box that takes "Brake (all), Left, right" and converts it to "Solid brake on the (non-blinking side) with (other) blinker on" at the trailer. I've seen corrollas with seperate amber turn signals, is why I ask.
Anyway that box might require a certain current pass-through to work, which LEDs are not demanding. Or it sucks "a little" current to work, which LEDs can't do without. Sort of like trying to run a motion sensor light with compact flourescent bulbs, the bleed-thru isn't right.
Anyway that box might require a certain current pass-through to work, which LEDs are not demanding. Or it sucks "a little" current to work, which LEDs can't do without. Sort of like trying to run a motion sensor light with compact flourescent bulbs, the bleed-thru isn't right.
Originally Posted By: eljefino
If your tow vehicle has seperate amber bulbs for the turn signals, there's a small diode box that takes "Brake (all), Left, right" and converts it to "Solid brake on the (non-blinking side) with (other) blinker on" at the trailer. I've seen corrollas with seperate amber turn signals, is why I ask.
Anyway that box might require a certain current pass-through to work, which LEDs are not demanding. Or it sucks "a little" current to work, which LEDs can't do without. Sort of like trying to run a motion sensor light with compact flourescent bulbs, the bleed-thru isn't right.
All I know is when I installed the lighting kit, it worked perfectly, and then about once every month or two I would experience one or both tail lights on the trailer either not working at all, or being lit very dimly. Usually, cleaning the grounding surfaces gets them back to working properly, but I did that this morning and it didn't fix it this time...it appears this time I have a bad harness, either on the trailer side or on the car side because it isn't a grounding problem. I just don't understand why these lights are so finicky...the lights on vehicles don't do this, why do trailer lights do it?
If your tow vehicle has seperate amber bulbs for the turn signals, there's a small diode box that takes "Brake (all), Left, right" and converts it to "Solid brake on the (non-blinking side) with (other) blinker on" at the trailer. I've seen corrollas with seperate amber turn signals, is why I ask.
Anyway that box might require a certain current pass-through to work, which LEDs are not demanding. Or it sucks "a little" current to work, which LEDs can't do without. Sort of like trying to run a motion sensor light with compact flourescent bulbs, the bleed-thru isn't right.
All I know is when I installed the lighting kit, it worked perfectly, and then about once every month or two I would experience one or both tail lights on the trailer either not working at all, or being lit very dimly. Usually, cleaning the grounding surfaces gets them back to working properly, but I did that this morning and it didn't fix it this time...it appears this time I have a bad harness, either on the trailer side or on the car side because it isn't a grounding problem. I just don't understand why these lights are so finicky...the lights on vehicles don't do this, why do trailer lights do it?
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dont forget about the car side. especially if someone used scotchlocks to tap into the wires.
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I just don't understand why these lights are so finicky...the lights on vehicles don't do this, why do trailer lights do it?
Trailer lighting is generally far less robust (in terms of durability testing, etc) than vehicle lighting is, and it's also exposed to much more corrosion. Your best bet for trailer lighting, at least in my humble opinion, is to buy from an OEM manufacturer (such as Petersen Manufacturing) and do your best to over-build everything. My trailer has four lamps (two amber side markers and two rear tail lamps). They all share one ground at the front of the trailer and I haven't had any issues with it. The trailer parks outside in the weather and gets used once every few months.
I'd still like to know if you have this issue if you wire the lamps direct to a battery. The diodes and resistors and all of the electronic circuitry to run the LED lamps are internal to the lamp housings, so you should be able to connect the lamps direct to battery to test them. Some of them even come with a 9V battery in the packaging allowing you to test them and see how bright they are.
I just don't understand why these lights are so finicky...the lights on vehicles don't do this, why do trailer lights do it?
Trailer lighting is generally far less robust (in terms of durability testing, etc) than vehicle lighting is, and it's also exposed to much more corrosion. Your best bet for trailer lighting, at least in my humble opinion, is to buy from an OEM manufacturer (such as Petersen Manufacturing) and do your best to over-build everything. My trailer has four lamps (two amber side markers and two rear tail lamps). They all share one ground at the front of the trailer and I haven't had any issues with it. The trailer parks outside in the weather and gets used once every few months.
I'd still like to know if you have this issue if you wire the lamps direct to a battery. The diodes and resistors and all of the electronic circuitry to run the LED lamps are internal to the lamp housings, so you should be able to connect the lamps direct to battery to test them. Some of them even come with a 9V battery in the packaging allowing you to test them and see how bright they are.
I have put LED lights on my boat trailer and will shortly put them on my 12K GVW flat trailer. Each has many lights. I only use Ancor adhesive lined connectors & liquid tape. No issues so far.
Forget those blue connectors where you squeeze the connector's contacts and then flip over the blue connector cover.
Forget those blue connectors where you squeeze the connector's contacts and then flip over the blue connector cover.
If I understand... You have check the connections on the trailer ie... Light to the trailer for the ground.
Have you check the ground connection on the truck/car side of the plug? If I remember right the the White is the ground and it should be connected somewhere close to the plug. Sometimes light trailers rely on the hitch to make the "ground" connection. This is not always reliable connection.
If you have a good ground connection I would get a battery charger and use that as your power source and ground to check the lights at the trailer plug. Some nails in the clamps of the battery charger can be used to make the connections. If the lights on the trailer work then you need to look at the wire harness on the truck/car...
Look at the plug harness connections to see if the are loose/dirty ect.
Have you check the ground connection on the truck/car side of the plug? If I remember right the the White is the ground and it should be connected somewhere close to the plug. Sometimes light trailers rely on the hitch to make the "ground" connection. This is not always reliable connection.
If you have a good ground connection I would get a battery charger and use that as your power source and ground to check the lights at the trailer plug. Some nails in the clamps of the battery charger can be used to make the connections. If the lights on the trailer work then you need to look at the wire harness on the truck/car...
Look at the plug harness connections to see if the are loose/dirty ect.
redid my trailer wiring this past summer. I ran all new wire through PVC pipe and have 3 separate grounds. Works great. Also bought new harness from tow vehicle to trailer.
Ancor adhesive lined connectors & liquid tape, like Donald said above. And do it yourself- will be done right and last alot longer!
Tinned wiring lasts longer too, especially in humid/water environments.
Have learned these things the hard way.
Tinned wiring lasts longer too, especially in humid/water environments.
Have learned these things the hard way.
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Nick1994
$100 site donor 2024
Sometimes the wire that comes in kits is junk. I bought a wire set on Amazon for my trailer and it is very high quality, not the thin junk wire I had from Harbor Freight. I too ran it in PVC. Hose clamped the PVC to the trailer frame.
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