is 12 volt line on the 7 pin connector hot?

[BigChick]

2015 ram 3500 dually - i took some readings today and the 12 volt auxillary lead on the 7 pin receptacle is hot even with the keys out of the ignition and the ignition off. we tow a trailer and i would like this lead to be hot only when the ignition is on? is there a relay or something that i can add that will control this lead to make it hot only when the ignition is on using the existing wiring? another option would be to rewire it to go through a spare upfitter switch. from what i have read some of these are only hot when the ignition is on.

 

[crash68]

You would need to install a relay to shut off the +12V on the trailer plug. If you used an upfitter switch those can be selectable to be On/Off with the ignition.
If your concerned about the trailer draining the truck battery, just pull the plug when parked overnight. You'll know it's not plugged in when the lights don't work and the factory brake controller states "No Trailer".

 

[lpennock]

You could put a Voltage Controlled Relay (VSR) where the camper cord connects to the camper electrical system. They isolate the truck when Voltage is below 12.8 and connect truck when Voltage exceeds 13.2v. Most only sense turn on Voltage on the truck side but there are a couple that will turn and charge your truck when your camper generator/solar gets camper side above 13.2v.

Sent from my SM-T500 using Tapatalk

 

[Tundra_Gone]

Just found this out about my truck today. ******** engineering IMHO!! Never owned a truck that output the power when the truck i not running. BTW First Ram.

 

[2003F350]

Just found this out about my truck today. ******** engineering IMHO!! Never owned a truck that output the power when the truck i not running. BTW First Ram.

Must be a young guy. There was once a time when, to get a 7-way RV plug on your truck, it didn't come on the truck from the factory. Either the dealer did it or a local trailer place did, and a LOT of those would pull the 12v directly from the vehicle battery. It wasn't until the towing package started including the electrical that the 12v was controlled by the key.

 

[Tundra_Gone]

If you call 67 young, yep I'm young! Yes I have done it all and towed with every vehicle I have owned but my first car, a 1967 Firebird. Had to mount hitches and wiring on several which I dd ALL the work. I remember when the first add on trailer wiring kits came out and had factory plugs and how easy those were. I had a 2003 F150 that did not have the actual tow package, but all the wiring was in the harness, so adding the plug was jut a matter of cutting off factory plug and splicing into wires. To get the 12 volt out to work I had to add a relay in the appropriate socket in electrical box under the hood. I am glad to see the power outlet on the dash, what us young folks called a cigarette lighter in the day, stays powered with the ignition off.

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[turkeybird56]

If you call 67 young, yep I'm young! Yes I have done it all and towed with every vehicle I have owned but my first car, a 1967 Firebird. Had to mount hitches and wiring on several which I dd ALL the work. I remember when the first add on trailer wiring kits came out and had factory plugs and how easy those were. I had a 2003 F150 that did not have the actual tow package, but all the wiring was in the harness, so adding the plug was jut a matter of cutting off factory plug and splicing into wires. To get the 12 volt out to work I had to add a relay in the appropriate socket in electrical box under the hood. I am glad to see the power outlet on the dash, what us young folks called a cigarette lighter in the day, stays powered with the ignition off.

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That outlet controlled by 2 position fuse. One way set, full time, other ignition only. On My 19, my fuse for that located interior box by steering wheel, LOL. Not know on 6.4, though I bet U already knew this, hee hee. Kinda posting more for folks who do not know.

 

[Tundra_Gone]

That outlet controlled by 2 position fuse. One way set, full time, other ignition only. On My 19, my fuse for that located interior box by steering wheel, LOL. Not know on 6.4, though I bet U already knew this, hee hee. Kinda posting more for folks who do not know.

Thank you, I'll check it out.

 

[Biker]

My issue is somewhat like the above.
I need to start out saying I bought the Lumber Wagon used. I do not have an owners manual. It is a 2012 Ram 3500 4x4 Dually I am looking for the fuse or fuses that control the always on pin on the 7-pin. It is the one that charges the trailer battery. It has worked until this last week and is no longer hot and no longer charging the battery. Would someone please let me know what fuse or fuse location to look for. If I am asking in the wrong location please move or delete.
Thank You.