This is a difficult problem, since neither you nor the people who want to help you know how your system is put together or designed to do. Coulda/woulda/shoulda don't matter right now because you're stuck without power.

Let's see if we can get you on your feet first, then we can worry about doing things the right way.

if it ever worked before and doesn't work now then at least one of these is probably true;

• something is unconnected: wiring terminal loose, fuse blown / breaker tripped
• something was inadvertently turned off by physical switch or app setting
• something has failed

It's also possible that it's working fine but you don't know it. Example: “my charger isn't charging my lithium batteries even though they are not at 100%”.

I encourage you to make a text document on your phone or PC to hold info on what we find in this section. Not only is it handy for you, but if you ever need help you can paste in the data so we can tell what you've got. win-win

Personal note: here is my own plaintext list, and a fancier version with commentary. I did not know this off the top of my head – I went through my amazon orders, emails, etc, to gather it all up.

It might be overwhelming to try to understand all at once, so start simple. Look around you. What can you see that might be electrical? Can you take and post pics if nothing else?

House (“living area”) battery banks are usually large and often the size and shape of the van starter battery you've seen under the hood. There are likely thick red/black cables connecting them to the rest of the system. There may be one or more batteries in the bank, and can be arranged in parallel or series.

* How many are there? * Do you see any capacity markings like Ah(amp-hours) or Wh¹⁾ * Do you see a model name, like Smart Lithium Iron Phosphate? * Do you see any charging guidelines on the lable?²⁾

Solar panels are usually pretty obvious if you have them. They may be mounted on a rack, adhered flat to the roof, or be portables/suitcases that store inside the van. The backside label will show the specs you'll need to know and share. If there is no back label you will need to consult the manufacturer's website or manual.

We recharge our battery banks almost every day, so there is probably at least one charger present. In order of most common to least common:

The solar charge controller will have wires coming into it from the solar panels, assuming they are permanently mounted. The other set of wires goes out to the battery bank.

Common brands are Victron, Renogy, EpEver. Morningstar and Blue Sky were premium controllers that are not as common in vans nowadays. There are also many rebranded inexpensive-but-functional controllers from SRNE, BougeRV, Eco-Worthy, etc.

The lowest end of the market is flooded with very cheap controllers (often incorrectly called “MPPT”) in the $10-$20 range. These can work if you understand their limitations.