Mine is a 2001 SR5. Never towed with it and I don't know if the previous owner ever did. Had someone check all 4 pins on the wiring harness with a Fluke multimeter and said they were fine, but I didn't personally see it. I built this trailer from a kit.
I have spent the past 2 days looking here and beating Google to death for an answer, and the closest I have found to my exact problem is "running lights work, but no stop or turn signals", well, mine is the exact opposite. Everybody else seems to have no lights or grounding problems.
From the wiring harness to the lights is yellow to yellow (driver), green to green (passenger), and brown to brown (tail lights), just as I have read about and seen in schematics.
Stop and turn work fine on the trailer. Running lights have never worked. Side marker are not hooked up yet. I checked the towing and tail fuses under the food. They are fine. Could not find any related fuses in the compartment by the steering wheel.
I don't think it is a ground problem because if it were, I would suspect that none of the lights would work. In fact, I have a separate black ground wire on each side going to the tongue, and when I disconnect it, nothing works, reconnect, stop and turn work, but not running lights.
I tried testing the 4 pin plug on my truck with a test light (I don't have a multimeter). No pins would make it light up, but yellow and green pins obviously work or else the stop and turn wouldn't work, so I'm doing something wrong.
Another thing I did just to see if there was any power to the brown wires is I plugged the brown harness wire into the yellow wire on the trailer, then turned on my headlights. Logically power should still flow and the bulb should light up. Nothing on the test light or light bulb itself. I switched it back to yellow on yellow. Stop and turn work again.
At this point the only thing I can think of is that converter box behind the cargo panel I just read about yesterday may be the problem. Have not looked into it yet.
Have I missed anything?
I have spent the past 2 days looking here and beating Google to death for an answer, and the closest I have found to my exact problem is "running lights work, but no stop or turn signals", well, mine is the exact opposite. Everybody else seems to have no lights or grounding problems.
From the wiring harness to the lights is yellow to yellow (driver), green to green (passenger), and brown to brown (tail lights), just as I have read about and seen in schematics.
Stop and turn work fine on the trailer. Running lights have never worked. Side marker are not hooked up yet. I checked the towing and tail fuses under the food. They are fine. Could not find any related fuses in the compartment by the steering wheel.
I don't think it is a ground problem because if it were, I would suspect that none of the lights would work. In fact, I have a separate black ground wire on each side going to the tongue, and when I disconnect it, nothing works, reconnect, stop and turn work, but not running lights.
I tried testing the 4 pin plug on my truck with a test light (I don't have a multimeter). No pins would make it light up, but yellow and green pins obviously work or else the stop and turn wouldn't work, so I'm doing something wrong.
Another thing I did just to see if there was any power to the brown wires is I plugged the brown harness wire into the yellow wire on the trailer, then turned on my headlights. Logically power should still flow and the bulb should light up. Nothing on the test light or light bulb itself. I switched it back to yellow on yellow. Stop and turn work again.
At this point the only thing I can think of is that converter box behind the cargo panel I just read about yesterday may be the problem. Have not looked into it yet.
Have I missed anything?
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