Trailer light help please?
#1
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Have LED trailer lights I just recently installed. When braking and turning both sides work fine. The running lights were not working and found a fuse on the Silverado that was blown. Replaced. Both sides brake and turn signal fine but only one side is lit up as running lights.
Any ideas?
Any ideas?
#2
Admirals Club 


Often these things are related to how the lights are grounded. Check there is a dedicated ground from each light that connects to the plug on the trailer and that the socket on your truck is properly grounded as well.
#3
Senior Member


And since you just installed them and they haven't worked and they are LED lights, try switching polarity of the wires to the non-lit running lights. Unlike incandescent bulbs, the diodes in LEDS require correct polarity to pass current .
#4
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Most all of the problems I have had with Trailer lights is the Manufacture using stupid un-sealed Butt connectors on the Wiring Harness!! Always a bunch of them inside the Trailer ,unseen. Lot of tie ins to the Main Harness! A Test Light is Your Friend!
#5
Admirals Club 


In addition to the ground wires that attach to the trailer frame, I ran another ground wire back to the tongue on each side, connected to the trailer frame and back to truck ground. In fact I threw away the 16 gauge "kit" and ran 14 gauge tinned copper with heat shrink butt connectors. 6 years and counting.
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#7
Admirals Club 


Ergo all lights are grounded to the trailer and the vehicle through a grounding "system." So if the ground on the frame on the Drivers side corrodes through, that light is still grounded to the tongue ground, the passenger side ground, and the vehicle ground. Make sense?
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The trailer plug has a ground wire that connects to the vehicle ground. That ground is attached to the trailer frame near the tongue. I cut that ground wire and spliced in two ground wires and ran one down each side of the trailer and spliced them to the ground wires coming off the lights. These are also attached to the frame near the lights.
Ergo all lights are grounded to the trailer and the vehicle through a grounding "system." So if the ground on the frame on the Drivers side corrodes through, that light is still grounded to the tongue ground, the passenger side ground, and the vehicle ground. Make sense?
Ergo all lights are grounded to the trailer and the vehicle through a grounding "system." So if the ground on the frame on the Drivers side corrodes through, that light is still grounded to the tongue ground, the passenger side ground, and the vehicle ground. Make sense?
#9
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Think I’m narrowing the problem down. The passenger running light wire (brown) is extremely hot to the point it melted the jacket. I’m only getting 8 volts when I disconnected it from light. What would cause this? I went ahead and cut it at harness and I’m getting 12 v now.
#10
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Sounds like resistance in the wire from corrosion, lots of corrosion. Skin some of it open and you'll see the metal is brown or green. Rip it all out and start over.
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Basically rerun that particular wire? Can I just jump off of the other running light? Running lights and brake lights are separate. LED lights.
#12
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See pics I posted on "Trailer rewire" thread
Last edited by China Rider; 10-24-2020 at 06:41 AM.