12v Stopped working in my Van

[Gravity2424]

So I wake up this morning to find none of my 12v appliances are working. I go to my solar controller and everything seems to be working fine. Indicator lights for the PV, batteries and the load all look fine (The solar panel indicator light may appear off in some of the photos because batteries are charged to 100% so the light will flash then). I cycles through some of the pages that show information on the load output but honestly I’m enough of a beginner to where I don’t know what they mean so hopefully someone can shed some light. I’ve checked all my fuses and I completely disconnected every wire and reattached them just to make sure everything was in order but still no power to the load.
One possible issue is that I thought it may be the ground wire and when I went to fix it it kind of got messed up so I reattached a new wire to the bolt attached to our frame (possible it’s not getting a perfect connection but I doubt this is it.) Another possible but unlikely situation is that I recently just replaced our water pump and when we leave the pump switch on on accident without using water the pump will severely overheat. I’m not sure if the pump was unintentionally left on or not. I stupidly do not have a fuse from the battery to the controller currently so who knows? The controller seems to be fine though there are no discolored or burnt areas, no alarming indicators or anything of the sort.
Here in the middle of the desert in Arizona after no issues for about 6 months and this all happens in the middle of the night a couple days after the last time we were driving so it’s not like any wires got knocked loose. Any troubleshooting ideas? Let me know if you need more pictures/ info. Thank you, sorry for the run on sentences!

 

[MichaelK]

First off, do you have volt/multimeter? Can you borrow one? If you can find a voltmeter, you can check each and every sub-assembly individually. Start with the battery. Before touching the battery though, disconnect the solar input from the charge controller. Then disconnect the connections between the controller and the battery.

Try disconnecting every wire, shining the terminals up, and reconnect. Can you determine the voltage of the disconnected battery? Once the battery terminals are clean and bright, reconnect the battery connections to the controller ONLY. Do not connect the solar panels. Let the controller boot up on battery power only.

After the controller is booted up, what is the battery voltage displayed on the controller? Now reconnect the solar input. Do you see a jump in voltage on the controller the moment the panels are connected? Check the voltage of the panels while disconnected, and again after you connect to the controller. Do you see ~18V while disconnected, but it drops back down to ~13-14V after connecting back up?

I'm guessing you have a loose connection somewhere that is not obvious. Disconnecting and cleaning every connection can help find a hidden bad connection.

 

[Gravity2424]

First off, do you have volt/multimeter? Can you borrow one? If you can find a voltmeter, you can check each and every sub-assembly individually. Start with the battery. Before touching the battery though, disconnect the solar input from the charge controller. Then disconnect the connections between the controller and the battery.

Try disconnecting every wire, shining the terminals up, and reconnect. Can you determine the voltage of the disconnected battery? Once the battery terminals are clean and bright, reconnect the battery connections to the controller ONLY. Do not connect the solar panels. Let the controller boot up on battery power only.

After the controller is booted up, what is the battery voltage displayed on the controller? Now reconnect the solar input. Do you see a jump in voltage on the controller the moment the panels are connected? Check the voltage of the panels while disconnected, and again after you connect to the controller. Do you see ~18V while disconnected, but it drops back down to ~13-14V after connecting back up?

I'm guessing you have a loose connection somewhere that is not obvious. Disconnecting and cleaning every connection can help find a hidden bad connection.

I did all of this and everything seems to be perfectly normal. I think it has to do with the connection between the positive wire for the load from the controller to the fuse box. The wires going into the positive terminal in the fuse box (see picture) look fairly frayed but most of this wiring is in the guts of the van where it’s pretty hard to access.
The photo I included of the fuse box is once I started to run our generator and you can see the green light labeled D19 will flicker on and off when working properly, occasionally I can get this light to be flickering for short moments but none of the 12v in the van will come on. I don’t know enough about how the generator is connected to the fuse box or how the fuse box is connected to the positive load on the controller.
Where the previous owner of the van attached the wire from the controller’s positive load is included in the last photo. I didn’t even realize this for some time, all I knew was the wire coming out from the wall was for the load only later did I realize it was attached like you see in the photo. I always assumed the wire went straight to the fuse box. (The green wire is the positive load coming from the controller) Any suggestions?

 

[chrisski]

I did all of this and everything seems to be perfectly normal. I think it has to do with the connection between the positive wire for the load from the controller to the fuse box.

That would certainly be something I'd fix.

Where the previous owner of the van attached the wire from the controller’s positive load is included in the last photo. I didn’t even realize this for some time, all I knew was the wire coming out from the wall was for the load only later did I realize it was attached like you see in the photo. I always assumed the wire went straight to the fuse box. (The green wire is the positive load coming from the controller) Any suggestions?

I would fix that.

If I'm following you correctly, the previous owner attached the solar charge controller to the positive side of the system this way. If this is true, I would rewire the SCC to the battery.

Whatever going on there, what appears to be solid strand wire folded over multistrand wire to get a good connection may be a field fix, but certainly not for extended ops. I'd attach it in another way like a bus bar.

 

[MisterSandals]

Somebody needs a different electrician:

 

[MichaelK]

In the blow-up the MS provided, I can see at least one strand from the frayed positive cable physically touching the fusebox box. Why it hasn't already melted I can't say.