Electrical question…

[ElGigante]

I have a new to me 06 Grandby shell. All the aftermarket stuff runs off the battery bank. Heater, extra outlets, one side light. However the roof mounted lights and the fan which are factory seem to only run if I hook up my truck to the wiring harness.

Does this mean that they will be running off my starter battery?

I will eventually be rebuilding the entire inside but for now we were just going to live with it as it is then see what our family really needs. I do not want to have the fans and overhead lights draining my battery though.

Can I check that with a multimeter? Will the Amps coming from my trucks battery change if I fire up the fans and lights?

Anyway I am more of a carpenter than an electrician but I figured this would be an easily answered question.
I searched the threads here and on FB to no avail.

 

[Vic Harder]

Welcome to the cult ElGigante. Sounds like the person who added the aftermarket stuff did not want to play with the existing electrical and left it as is. What that means is that the connection to your truck does two things:
1) It allows the truck to try (it doesn't do a good job of that) and charge your camper battery while the truck is running
2) It powers the running lights (if you have them)
3) It powers the basics of a shell, the fan and overhead lights.

If you can follow the wiring after it comes into the camper, it will eventually lead to a smallish 30A thermal breaker, and from there to a battery separator, which is designed to keep your two systems (truck and camper) from totally draining each other. When either end is receiving a charge, it is supposed to connect the two systems together so that they can both charge.

Before saying much more, can you confirm all of the above?

 

[ElGigante]

Thanks so much. This makes sense for sure. I will look tomorrow. And see if I can follow the lines. The problem is the owner before built cabinets and put lots of the wiring behind and the cabinet for the battery is a bit of a rats nest.

Thanks again for taking the time. I’ll take a bit of mine look and get back to you. I do feel better now though. It did seem weird that the two were separated and that FWC would allow for the starter battery to run the campers basic functions.

 

[Wandering Sagebrush]

Hi ElGigante, welcome to WTW. Vic nailed it. A possible quick way to determine if the truck is charging the battery is to check camper battery voltage with the truck off, then again with the truck running. There may be a switch that connects the charging circuit to the battery.

 

[Old Crow]

You might take a look at this post for help in your wire-tracing efforts. You may be able to see the yellow wire running along the cabover floor in the left-front of the camper and then down into a cabinet.

Tech Tip / Service Bulletin (Camper to Roof Wiring)

I'd also look for yellow at whatever fuse panel(s) you have.

Also- there's a truck-to-camper wiring diagram in this post to help you see what wiring to the battery separator often looks like.

Steps for wiring truck pdf

 

[Machinebuilder]

I wonder if the camper had a battery from the factory.

 

[Jon R]

I wonder if the camper had a battery from the factory.

I’m thinking it didn’t.

 

[ElGigante]

Sorry guys. Life’s getting In The way today. Taking the kids disc golfing. Hopefully time to check later.

 

[Wandering Sagebrush]

Sorry guys. Life’s getting In The way today. Taking the kids disc golfing. Hopefully time to check later.

No worries, have fun with the kids.

 

[ElGigante]

Ok. I had a few mins to look at the wiring. The main wire in from the plug goes immediately behind the original particle board. You can see that in picture 1.

Also I’m picture 1 you can see smaller gauge orange and black wires leading to a switch and a 12v outlet. These appear to be stock but moved by the previous owner to outside a cabinet he built.

You can see that in picture 2. In this picture the to 12V the previous owner must have added. It works even when not hooked up to truck and is run by the larger gauge red and white wires at the top of picture 1 to the battery bank. Going through a fuse box that the previous owner installed to run the propane heater and a water pump. See picture 3.

There is one set of yellow and black wires that comes from behind the carpet and goes behind the front hinge that looks factory and no doubt powers the fan and two lights on the roof. This only works when plugged into truck harness. Picture 4.

It looks to me like the previous owner either moved the battery that came with the camper or that the camper came without a battery. The new system he put in looks like it is set to only work of shore power and solar charging. Both of which he put holes In The camper to install exterior plugs. See pictures 5 and 6.

Seem like I will need to redo the whole thing at some point and In the mean time just get a portable solar panel to charge batteries for now.

I will check the voltage of batteries when hooked up to truck without truck on. Then turn on truck and check again. Hopefully this will let me know if a connection still exists between the two. If not I’ll have to assume the starter battery in my truck is running the lights and fan? Gosh I hope not lol.

The next step after that would be to start removing some of the after market cabinets and such to get a better look behind the paneling at the stock wiring.

Thoughts? Thanks in advance.

Ps. Sage I assume you’re the guy who put up the YouTube videos last year of your build out. I liked them. Was gonna model our design of yours. We are ultra lighters so we can do without most of the stuff people put in their bulldogs these days. But I probably will over build for 2 lithiums and a decent inverter. Putting 200-400 watts on the roof at some point down the road.

Likely I’ll keep the propane heater (if it works well at altitude)

 

[ElGigante]

Sorry I was not able to Confirm all that you said in your post yet Vic. And actually test the battery like sage suggests. I’ll be looking to do both soon enough it I did t want to leave you guys hanging.

 

[ElGigante]

Pps. Couldn’t post pictures. Do I need to do it from a computer? I’m on an IPhone.

 

[ElGigante]

Pictures

 

[ElGigante]

I think I got the pictures to get them all in on one I had to make them smaller. If you guys need better pictures let me know. Thanks

 

[Wandering Sagebrush]

EG, I’d like to take credit for the YouTube build, but alas… I must be honest, t’was not me.
I’m having a hard time figuring out what you have, but it looks like quite a job. With respect to pictures, to get the best display, I recommend you upload to a personal gallery here on WTW, or use a hosting site like Flickr, then select the address of the photo, and use the picture icon in the full editor menu bar. Your profile has a link to where you can create your gallery, then upload to it. The address is where the picture is stored, and can usually be found by clicking on the photo, then right clicking on the larger image, and selecting something like “copy image location/address”. That can be pasted into the picture icon dialog box. The results look like this…

There are pinned threads in the member support forum that help with this. If you have trouble, send me a message, and we can work through it. BTW, any cell phone isn’t the easiest way to post.

It looks to me like you may have flooded batteries versus AGM batteries, which I’m sure you know can out gas hydrogen that could lead to an explosion if confined in a small area. Probably wouldn’t happen in a shell, but you never know.

You might start by drawing a wiring schematic of what you want your system to look like electrically, and determine where you want your components to reside.

The cable coming from behind the lift board is for marker lights and apparentl the fan, and possibly to a solar plug (or solar wiring that is terminated near a fan or vent).

The photo of the batteries appears to have a small charging unit that may be connected to the plug that is near the truck connector in your last picture.

I’m going to stop typing, and spend a bit more time looking at your pictures. Hang in there…

 

[ElGigante]

Yeah. I think they are marine 6v batteries wired together to make 12v. Could be flooded as he put a vent out of the battery box through the back of the camper wall. Just pvc.

Again. This system will ultimately be replaced with a lithium set up. But I was hoping to “get by” for 6 months or so of trips till I can really get an idea of what we want to run in there and what layout we want for the camper I’m general.

By get by I just meant not kill my starter battery on my first trip out using the fan and overhead lights lol. It worked fine the last few trips without being hooked up at all. Just one light a couple 12v outlets and the heater and stove

 

[Wandering Sagebrush]

<snip>
By get by I just meant not kill my starter battery on my first trip out using the fan and overhead lights lol. It worked fine the last few trips without being hooked up at all. Just one light a couple 12v outlets and the heater and stove

You could look for the fan and interior overhead light circuit, and move them to the internal 12 VDC bus.

 

[Vic Harder]

You could look for the fan and interior overhead light circuit, and move them to the internal 12 VDC bus.

I think that is what his original post was wanting to know how to do. What you said above about the cable looms going behind the lift panel is likely correct - those wires are for the overhead lights, fan and also for roof mounted solar panels.

I also believe that if the camper shell had no factory installed battery, that the fuse for those circuits was in the truck's trailer harness, not in the camper. Please correct me if I am mistaken. If I'm right, it isn't as simple as pulling a fuse to determine where the power is coming from.

The pictures are kinda fuzzy. Will look again later.

 

[Vic Harder]

OK, clarify please. Are the first pic and last pic related? As in, inside of camper and outside of camper on the same plugs/wiring? That upper plug looks like an AC plug, and if so, likely feeds that one of hte black boxes in the pic with the batteries, and is an AC/DC charger.

That same battery pic, has what looks like a thermal breaker at the top right.

What is the round thing in below that on the far right? A gauge? A plug?

In the same pic, I see multiple red wires on the left most battery's +ve post. One goes to that breaker, another to the "ac/dc" charger, and another to a solar device? Do you have solar panels? Or is that another battery?

I note a LOT of red and white wires. Do yourself a favor when rewiring this, and settle on a common color for ground (your system is using both white and black for ground), and then a different color for the positive wiring for each circuit. For example, light blue for your fridge, orange for 12 & 5v power sockets, etc. Makes tracing wiring a lot easier.

As was said above, follow the wires that are in that wiring loom behind the push panels back to their source. They will go along the 4" high trim panel on the cabover, and then down to the carpeted bench area. In my campers, while going down that length from bed to bench, one of the wires was screwed into the frame tubing to provide ground, and the other went to the plug and got power from the truck. If that is the case, on yours, that is where you need to break the circuit. You can test this without pulling the cabinets apart!

Testing:

1) disconnect internal batteries. Lights/fan still go on, Yes? If so, disconnect truck/camper. Lights/fan off, Yes? OK, then things are as described above.

2) at the plug where truck/camper connect, use VOM to find the "hot" wire from the truck. Disconnect just that wire, and check if the lights/fan now go off. If so, then run a wire to the wire you just disconnected to the fuse panel in your battery box. If NOT, then power is coming from elsewhere...

 

[ElGigante]

Ok to clarify as the pictures didn’t end up in order. (I will try and do a better job posting them next time) the last picture is the back right exterior of the camper he has an older 4 prong solar input here that is wired straight through to the battery bank. ( Above that is the PVC vent for the battery box on the other side of the rear right camper wall) To the side of those is a Shore plug that looks to go to an AC outlet inside which powers the solar charger… it’s plugged in to an AC outlet on the battery boxes exterior (though inside the camper… not pictured)

The second to last picture is directly through the wall from the last picture. So the wires you see come in are from the solar to the battery and from the shore power to to inside outlet. It wasn’t clear to me if they did anything else.

Top right in that second to last picture is a fuse. Top left is a power inverter. Below that left is the Solar charger. Below that the grey box is the back side of an outlet. It seems to be where the shore power wires go. A plug on the opposite side not pictured runs back into the battery cabinet through another hole to power the solar charger.

The third to last picture is of the fro t left going up to the fans and lights. No solar plug up there on this model. (That sux) from here they run behind the carpet and back toward the main area of the camper I’d guess but I will be taking things apart to find out where they go.

The first picture bottom left is the large grey main cable that comes into the camper for the exterior here the is immediately run behind the wall of the camper again never to be seen again. You get a 1” view of it lol.

The red and white wires at the top run from the battery’s and were put in but the first owner. That 12v plug works and runs the fridge. The orange and black ones blow run to another 12v plug with an on off switch that only seems to work when plugged into the truck. That’s factory though its location was moved.

Picture two is directly outside the cabinet front left of camper where those plugs are pictured. The top is always on and running from the battery the bottom has a switch and only works when the camper is connected to the truck.

Picture 3 is the fuse box in the center left of the camper at the stove and water pump and heater. They all seem to work fine… though I have the water pump off because there is no water tank hooked up. (I may do this later too)