Trailer constant hot

kzlucas · April 4, 2020

Truck is a 2014 Silverado 1500 LTZ. It is used with a slide in truck camper. The camper connects to the truck through the factory trailer 7-way plug. The battery terminal on the trailer plug is constant hot. This allows the camper to drain the truck battery when the key is off. I’d like to add a relay to the constant hot to turn it off when the key is off. This way it will charge the camper battery while running and not drain the truck battery when the key is off. I’ve been looking at simple 12v 30amp relays (little black cube) to put inline with the constant hot. I need to find a switched NON-CRITICAL power source to activate the relay. Any suggestions for the switched power source (preferably under the hood)? Also any suggestions to finding a good location to insert my relay in series with the constant hot wire?

In the fuse box under the hood I’ve noticed fuse #39 is labeled miscellaneous/ignition. What is this used for? There are also a few spots labeled upfitter. Would any of these locations be a proper spot to use an add a fuse tap to get my switched power source? Constant hot for the trailer is a 30amp fuse in position 2.

Edited April 5, 2020 by kzlucas

2kwik4u · April 5, 2020

I don't have much help for you on where to grab a constant hot (although I agree with the premise and think it's a great idea).

I'm just curious which slide in you're running on a 1500. Wife and I have been looking for a 1/2ton acceptable slide in for awhile. Any thoughts?

silveradosid · April 7, 2020

why not put a disconnect in the camper

kzlucas · April 13, 2020

On 4/5/2020 at 7:40 AM, 2kwik4u said:

I don't have much help for you on where to grab a constant hot (although I agree with the premise and think it's a great idea).

I'm just curious which slide in you're running on a 1500. Wife and I have been looking for a 1/2ton acceptable slide in for awhile. Any thoughts?

I have a Hallmark Guanella. I will be a bit overweight when it is fully loaded. There are a few good manufactures that make 1000lb slide in popup campers for 1/2 ton trucks. Four wheel campers, ATC, Phoenix, Bundutec, NorthStar, Outfitter. Lots of custom options on their base models.

kzlucas · April 13, 2020

On 4/7/2020 at 4:18 AM, silveradosid said:

why not put a disconnect in the camper

I have a disconnect in the camper now. As long as you remember to turn off the switch you won't end up with a dead truck battery 50 miles up a dirt road somewhere at a campsite. Having it switch off automatically could save a lot of trouble. If you don't remember to turn the switch back on when traveling you loose the opportunity to have the truck charge the camper batteries so you are topped up at the next camp site.

2kwik4u · April 13, 2020

7 hours ago, kzlucas said:

I have a Hallmark Guanella. I will be a bit overweight when it is fully loaded. There are a few good manufactures that make 1000lb slide in popup campers for 1/2 ton trucks. Four wheel campers, ATC, Phoenix, Bundutec, NorthStar, Outfitter. Lots of custom options on their base models.

Thanks for the feedback.

We're on the fence between RTT and a slide in at this point.

diyer2 · April 13, 2020

My 2 cents.

Slide ins are cramped IMO. Plus they are harder to load than hook up a trailer.

Slide ins you always haul with you.

Trailers are easier to hook up.

You can unhook and leave a trailer while touring around with the truck.

Better mileage, easier to maneuver.

Had a class A motor home also.

Truck and trailer were my favorite.

2kwik4u · April 13, 2020

45 minutes ago, diyer2 said:

My 2 cents.

Slide ins are cramped IMO. Plus they are harder to load than hook up a trailer.

Slide ins you always haul with you.

Trailers are easier to hook up.

You can unhook and leave a trailer while touring around with the truck.

Better mileage, easier to maneuver.

Had a class A motor home also.

Truck and trailer were my favorite.

For us.....tow behind camper, and driveable camper is out. Have a boat to take with us that is the primary objective. It's either tent camper, Roof Top Tent, or Slide in for us.

If we get a slide in, we'll take it out of the truck for the weekend at the campground. Leaving the truck to launch/retrieve the boat and run around.

Leaning hard towards a Roof Top Tent due to cost/complexity and payload issues with the 1500 pickup. We'll see how that shakes out though. Gotta get out of lock-down before we can do anything at this rate.

Edited April 13, 2020 by 2kwik4u
Spelling.....I'm not great at it.

x219c · April 20, 2020

If I were you I’d look for a fuse that is tied to the RAP (retained accessory power) system. Since you’re using a relay, it should introduce very little draw to the circuit. I’m not familiar with the box under the hood, but I’ve done the same tap in the driver side fuse panel inside the truck. There’s probably other options too, that’s just the one I’m familiar with.

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kzlucas · May 4, 2020

On 4/19/2020 at 10:26 PM, x219c said:

If I were you I’d look for a fuse that is tied to the RAP (retained accessory power) system. Since you’re using a relay, it should introduce very little draw to the circuit. I’m not familiar with the box under the hood, but I’ve done the same tap in the driver side fuse panel inside the truck. There’s probably other options too, that’s just the one I’m familiar with.

Sent from my iPhone using Tapatalk Pro

To follow up. I did end up using the RAP terminal located in the drivers side fuse panel. Ran a wire back with a fuse to the relay. Installed the relay between the trailer plug connector and the camper plug (this leaves the trailer plug constant hot and the camper plug switched).