Dash keeps showing light problem with trailer when there is none?

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Oldfart

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I towed my landscape trailer for the first time today. Every time I stopped, I got a light on the dash that said my left trailer light has failed. If I pressed OK, it would turn off until the next time I came to a stop. All lights on the trailer work as they should. Any ideas what to check, or is this a take it to the dealer thing?? I figured I would ask in here in case it's something simple I can take care of. Thanks.
 

CoronaRaptor

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Does it do it when you are just sitting there at home with it plugged in or just when you are driving? Try another trailer at uhaul or something and see if it repeats itself, if not, it's your trailer.
 
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Oldfart

Oldfart

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Does it do it when you are just sitting there at home with it plugged in or just when you are driving? Try another trailer at uhaul or something and see if it repeats itself, if not, it's your trailer.
It is fine if I'm just sitting. Once you drive and activate the brakes to come to a stop, the light comes on saying that the left light on the trailer is not functioning properly. I have running, brake, turn signal, and flasher lights, all working normally on both sides of the trailer.
 

CoronaRaptor

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Just do what everybody else does, drive without the trailer plugged in, lol. I guess if you take it to the dealer , you’ll have to bring your trailer with you. These new trucks are so high tech, but I would think it’s the plug, a loose wire or something, it’s seeing a voltage drop I would imagine.
 

KAH 24

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I towed my landscape trailer for the first time today. Every time I stopped, I got a light on the dash that said my left trailer light has failed. If I pressed OK, it would turn off until the next time I came to a stop. All lights on the trailer work as they should. Any ideas what to check, or is this a take it to the dealer thing?? I figured I would ask in here in case it's something simple I can take care of. Thanks.
@Oldfart I’d guess a minor wiring issue—my best assessment is there is something of that nature (moisture/humidity). This happens occasionally to my family RV tow rig.

My approach is to check the wiring harness and seal/waterproof connections— everything up and down stream. It could be a loose connection

No guarantees, but if you have time to tinker with it—please try that
 
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wheelman55

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Oldfart…I used to get that same message when I towed my double axle hd trailer. I improved some connections and now the message is intermittent. I check the lights whenever I get the message and they are all working. In my case I believe that I’ve got a gremlin in the trailer wiring. I will eventually re-wire the trailer.

Let us know what you find out.
 
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Oldfart

Oldfart

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@Oldfart I’d guess a minor wiring issue—my best assessment is there is something of that nature (moisture/humidity). This happens occasionally to my family RV tow rig.

My approach is to check the wiring harness and seal/waterproof connections— everything up and down stream. It could be a loose connection

No guarantees, but if you have time to tinker with it—please try that
Oldfart…I used to get that same message when I towed my double axle hd trailer. I improved some connections and now the message is intermittent. I check the lights whenever I get the message and they are all working. In my case I believe that I’ve got a gremlin in the trailer wiring. I will eventually re-wire the trailer.

Let us know what you find out.
Thanks, I'll have to start digging around.
 

PorterW1111

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I towed my landscape trailer for the first time today. Every time I stopped, I got a light on the dash that said my left trailer light has failed. If I pressed OK, it would turn off until the next time I came to a stop. All lights on the trailer work as they should. Any ideas what to check, or is this a take it to the dealer thing?? I figured I would ask in here in case it's something simple I can take care of. Thanks.
easiest solution would be to unplug the trailer... **** no more warnings... lol

on a serious note though have you checked the plug itself any dirt/dust in there that may be causing some resistance. maybe the taillight wire has a small internal break.

-dirty plug
-pinched wire
-internal broken wire strands


my guesses..
 
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Oldfart

Oldfart

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easiest solution would be to unplug the trailer... **** no more warnings... lol

on a serious note though have you checked the plug itself any dirt/dust in there that may be causing some resistance. maybe the taillight wire has a small internal break.

-dirty plug
-pinched wire
-internal broken wire strands


my guesses..
Thanks, I'll be doing that when the weather breaks here. One of my buddies also suggested putting some dielectric grease on the trailer plug after I make sure it's extra clean. He said one of their work trucks did this and the fresh grease fixed it.
 
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