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7-Way Trailer Connector Not Charging Battery

defran02

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I don't have a Gen14 yet, but on my 2015, the trailer 7-pin cable only energizes the 12V pin after a trailer has been detected and is put into drive or reverse for three seconds. If you just measure the output without a trailer connected, you'll never get a reading.
Would it stay on after that if you put the truck back in Park? Tomorrow when we leave for the next campground, I can test the trailer battery lead for >12.0V after connecting and driving a few feet and leaving the truck running. However the battery was reading 10v after driving for 6 hours.... and the trailer being recognized by the truck.
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Geo

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On mine I did the whole trailer set up thing, and I had to plug the trailer receptacle into my truck several times before I had 12 volt power. Once I got 12 power at the trailer I would have power at the trucks receptacle. Maybe I had a poor connection. After I finally got it to recognized the trailer it has been fine [slow learner I guess].
 

kdkool

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Once the 12V on the trailer harness turns on, it'll stay on even if it's placed back into park. You don't actually have to move the vehicle to turn on the 12V, just shifting to reverse or drive for 2-3 seconds is good enough.

Your problem might actually be that the battery in your trailer is defective. If you're at a campground with power, plugging in your trailer to shore power should also charge your batteries.

Our 2020 31ft international had a defective continental battery (there are two in parallel, one was pulling the other one down) right off the lot.
 
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defran02

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This is why I travel with a multimeter. Was showing 13 volts on the battery this morning when connected to shore power at the campground. Disconnected from shore power, and got 10 volts. Plugged in the trailer, selected the active trailer, put it in drive, and then back into park. Went back to the trailer and was showing 13 volts. ........
So I have a bad battery. And funny was that each time I was testing before, the truck was off. Once again not the truck's fault.
 

kdkool

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This is why I travel with a multimeter. Was showing 13 volts on the battery this morning when connected to shore power at the campground. Disconnected from shore power, and got 10 volts. Plugged in the trailer, selected the active trailer, put it in drive, and then back into park. Went back to the trailer and was showing 13 volts. ........
So I have a bad battery. And funny was that each time I was testing before, the truck was off. Once again not the truck's fault.

Glad you got it all figured out.
 

Roz_359

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I have a implement trailer with a power jack that plug in to a 7 pin. The trailer has surge hydrolic brakes so it just uses the 4 pin for lights. I can’t get the jack to work on my 21 150 where my 15 250 don’t have the smart electric. The 30 amp fuse under the hood is good. I can’t imagine you have to do a song and dance to get power for a jack to work.
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