Long shot – Switched 12v live, Citroen Jumpy/Dispatch 2015

I know, but this place seems to attract people with weird, niche knowledge, soooooo…

I have found a bunch of permanent 12v live feeds in the front part of my van, but the split charge thingy needs a switched live so it knows when it to start throwing current at the leisure battery. My plan was to hide the Renogy unit under the passenger seat (conveniently very near the vehicle battery and 12v/ground) with main 40A trips at the side for easy access, but I cannot find a switched 12v near there.

Should I just give up on the idea and break into the main fuse box?

My electrical knowledge is not amazing so I may be misunderstanding your Q

However, my split charge was just connected directly to the battery on my Ducato (big cable with appropriate fuses). I ran a cable under the cover into the battery box.

Now replaced with a dc to dc charger wired the same way. I didn’t locate a switched live.

Split charge won’t draw power without the engine running.

Not sure on the specifics of your setup but split charge normally doesn’t use a switched live, rather a feed that is live when the alternator is charging. Otherwise you could have your ignition in the ACC position and the batteries will be connected but the engine not running.

When I did a van conversion years ago I used a voltage sensing relay to provide the switch signal rather than having to find the alternator wire.

My new (to me) prado has a second battery, that uses a DC-DC charger, it was fitted by the previous owner and I wasn’t even aware such things existed until I found the battery and charger in the engine bay, no idea how this setup works!

I had a split charger with a VSR in my T5, but went for a DC-DC system this time (Renogy) that also supports MPPT for solar (if I ever get around to it). I have battery and ancillary fusebox ready to go, but the system needs a feed that (I think) is live only when the ignition is on.

I could have used a VSR, the alternator is not one of the newer smart ones, but I can re-use the charger on something later on that is newer. Look at me thinking of the future, but screwing over present-me…