Trailer running lights

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Jul 25, 2010 | 04:11 PM

Eric H

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From: Minneapolis

Trailer running lights

My trailer connects with the 7pin harness. Last night I lost the running lights. Turn signals, brake lights and trailer brakes still work.

Voltage at the 7pin is 12v for the brakes/turn signals. However voltage is below 1v for the running lights pin. Is this normal? Does a trailer need to be connected to activate the running lights?

I'm trying to isolate the problem between the truck and the trailer. Any tips? Also, are there certain fuses or relays I should check?

Thanks in advance

Jul 25, 2010 | 04:18 PM

nissandoc

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From: North Cackalacky

There are fuses in the fuse panel under the steering wheel. not sure which ones, you'll have to check the owners manual, it lists which fuse is which.

Jul 25, 2010 | 05:01 PM

Deluxe06

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From: Albemarle NC

I had this problem a few years back it was a fuse in the fuse box in the engine compartment don't remember witch one thowe.

Jul 25, 2010 | 05:47 PM

Eric H

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From: Minneapolis

Owners manual... Yeah, I should have checked there first.

on my 2001, the running lights are on fuse #4 (20amp) in the engine compartment. I'm not sure what caused it to blow, but the lights are working now. Hopefully it was just a one time occurence.

Jul 25, 2010 | 07:27 PM

racincowboy

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From: Happy Valley Or

Quote:

Originally Posted by Eric H

Owners manual... Yeah, I should have checked there first.

on my 2001, the running lights are on fuse #4 (20amp) in the engine compartment. I'm not sure what caused it to blow, but the lights are working now. Hopefully it was just a one time occurence.

My truck used to do that once in a great while. I discovered who ever had wired my trailer plug on the truck had a wayward single strand of wire that would ground out inside the plug and pop the running light fuse for the trailer every once in a while.

I dont know if this is true about our trucks a friend of mine had a 97 powerstroke with an auto trans and if his running light fuse blew and his truck was in park it wouldnt come out of park until he replaced the blown fuse. Go figure?