Puzzled by trailer lights not working

[drsportster]

Okay I have a kayak trailer all new lights and wiring .Then I have a motorcycle /atv trailer If the bike trailer is plugged in to my Chevy truck it lights all lights work same out put plug on the Kayak trailer has no lights The trailer lights are LED and there is no way to open an d inspect Solid sealed units White wire is ground Truck plug is hot Why would brand new lights with a brand new harness not work . How do you troubleshoot something like this Very annoying brand new stuff Help !

 

[Earl Grey]

Confirm that you have a good ground, the way I do it is using a jumper cable from the truck frame to the trailer frame.

 

[Loosehandle]

Okay I have a kayak trailer all new lights and wiring .Then I have a motorcycle /atv trailer If the bike trailer is plugged in to my Chevy truck it lights all lights work same out put plug on the Kayak trailer has no lights The trailer lights are LED and there is no way to open an d inspect Solid sealed units White wire is ground Truck plug is hot Why would brand new lights with a brand new harness not work . How do you troubleshoot something like this Very annoying brand new stuff Help !

It only takes a few days for mice to start in on new soy based wire.

 

[Powered By IH]

Try this, that eliminates the vehicle as a problem.

EDITED: Oh, and this is not me.

YouTube video

 

[Jim.ME]

Use your ohmmeter/continuity tester and see if there is continuity between the truck plug socket ground terminal and the frame. Then use your ohmmeter/continuity tester and see if there is continuity between the trailer plug ground terminal and the trailer frame. Are the lights grounded with separate wires or through the base of the lights? If you are not using a battery, as suggested by Powered by IH, to check the trailer wiring it is best to do testing of trailer electrical with the trailer close enough for the wire to reach the truck, but the trailer not connected to the truck hitch, that way you don't see a ground through the hitch. You need to prove the ground through the ground wire. A ground through a hitch is just a bonus backup.

 

[Mule Meat]

Did you test the lights before you installed them by using a good battery and a couple of jumpers?

Could be a bad set of lights.

 

[MarkB_MI]

One trailer is getting a ground through the hitch and the other is not.

 

[da.bees]

Use your ohmmeter/continuity tester and see if there is continuity between the truck plug socket ground terminal and the frame. Then use your ohmmeter/continuity tester and see if there is continuity between the trailer plug ground terminal and the trailer frame. Are the lights grounded with separate wires or through the base of the lights? If you are not using a battery, as suggested by Powered by IH, to check the trailer wiring it is best to do testing of trailer electrical with the trailer close enough for the wire to reach the truck, but the trailer not connected to the truck hitch, that way you don't see a ground through the hitch. You need to prove the ground through the ground wire. A ground through a hitch is just a bonus backup.

That is good advice that is often ignored or not understood. Multimeter is your friend and without one is like working in a dark room.

 

[cwtech]

Okay I have a kayak trailer all new lights and wiring .Then I have a motorcycle /atv trailer If the bike trailer is plugged in to my Chevy truck it lights all lights work same out put plug on the Kayak trailer has no lights The trailer lights are LED and there is no way to open an d inspect Solid sealed units White wire is ground Truck plug is hot Why would brand new lights with a brand new harness not work . How do you troubleshoot something like this Very annoying brand new stuff Help !

LED lights will not work on reverse polarity. ....Is it possible they are not wired correctly?

I would suggest disconnecting the trailer from the truck and using a battery to connect to the LED wiring. ....If they don't light, try reversing the polarity. .....Most LED's are not damaged by reverse polarity, they just don't work.

I seem to remember buying some LED lights and they operated opposite of what seemed logical color coding.

 

[Charles in Aus.]

Like others I suffered the annoyance of a faulty LED trailer light .
Brand new Range Rover , lights would malfunction , disconnect trailer all would be good
Rather than fuses it had an auto reset breaker for the trailer .
After a complete in desperation rewire I finally traced the fault to a licence plate light that had the incorrect colour coded wires , swapped them over and all was well .

 

[JOCCO]

Well first take a battery and pos neg to light to confirm it is working on or off the trailer. Then trace it out.

 

[drsportster]

The harness has power back at the taillights.What are the odds of all four lights not working ? I will try and reverse polarity on the lights

 

[NDIHC]

I'm about ready to buy a wireless trailer light kit so I don't have to keep lights working on several trailers. Which would be fine except for trailers with brakes.

 

[Hoenes]

If you're using the adapter for Chevy, (Round, to 4 wire flat) they now have them with indicator lights, built in. Shows that the truck is all correct. (Kinda like the test light for home circuits) At least that would eliminate the truck, itself.

 

[Earl Grey]

If you're using the adapter for Chevy, (Round, to 4 wire flat) they now have them with indicator lights, built in. Shows that the truck is all correct. (Kinda like the test light for home circuits) At least that would eliminate the truck, itself.

The other trailer works fine, that rules out the truck!

 

[drsportster]

The adapter has a small red light so the adapter is hot They wires are now new at the tail light you have no power from harness Another weird thing {I no longer assume all led lights are not working All four can't be bad so that is ruled out [ But the lights don't light when a battery charger is put to them I am still confused I even ran an auxiliary ground from trailer to truck.

 

[Jim.ME]

The adapter has a small red light so the adapter is hot They wires are now new at the tail light you have no power from harness Another weird thing {I no longer assume all led lights are not working All four can't be bad so that is ruled out [ But the lights don't light when a battery charger is put to them I am still confused I even ran an auxiliary ground from trailer to truck.

Do the lED lights light if you hook them direct to a battery? There may be an issue with the charger seeing the very low draw of an LED. This will also confirm which wire is ground.

Are these turn signal as well as taillights (3 wires in each light) or single function lights?

What is the socket on the truck? Flat 7 blade or something else?

Now you say there is no power in the harness. It reads like you are you using an adapter in the truck socket. I have had a cheap adapter let a blade slide back inside the adapter and loose contact. Have you used a test light or voltmeter to see if power is coming out of the adapter on the correct terminals for the lights the matching wires go to?

Is the ground carried through from the truck socket to the trailer plug and then to the trailer frame?

Are the lights grounded to a wire going back to the point the ground from the truck attaches or just grounded to the trailer frame?

Can you post the info on the lights you installed so we can see the lights you are asking about?

 

[TerryfromSWIowa]

Instead of battery charger why not use a drill battery to test? most LED's can handle 18 volts.

 

[rustred]

just get a 12 volt battery out of something and use that as your power source for the trailer lights. and a booster cable for the ground. then check to see if the lights work which they will.

 

[showcrop]

I have had various trailers that came with the lights wired in the standard format so I just plug in and they light. One came different from the factory. You can't count on everyone being on the same page.