Are the 12V sockets in the dash powered by the engine battery or the leisure batteries?

Mehdime · Jun 22, 2022

Hi,

The received wisdom on this forum is that everything ahead of the B pillar (I.e. everything in the cab) is powered by the engine battery (except for the inverter socket) and everything behind (I.e. in the camper area) is powered by the leisure batteries. Even California Chris states this in his video on the California electrics.

Yet, the manual of my T6.1 Ocean is very clear: *all* the 12V sockets are in fact powered by the leisure batteries. It explicitly lists them to avoid any confusion and both tm12V sockets in the dash are listed as being powered by the leisure batteries.

It makes sense to be honest because otherwise, there would be no accessible 12V socket to use to power e.g. a laptop when camping (the one underneath the back bench isn’t really accessible - no space to plug a USB-C PD adapter plus a USB-C cable).

So who is right? And how can we find out?

Ch1pbutty · Jun 22, 2022

On T5.1...one dash socket is main battery, the other is from leisure battery; All others are from leisure. T6 might be different and sometimes wiring may differ between individual vans.

Easy way to check is to get something like the below, plug it into the dash socket(s) (20 mins after engine is not running), and then charge a few things in from other/rear sockets in the van & then check the display voltage. If voltage drops then its running off the same battery as the charging items. If no change in voltage then the socket is running off the engine battery....so avoid leaving things plugged into this socket whilst camping! :

https://www.amazon.co.uk/dp/B07H2VDPNF/?tag=eliteelect-21

Mehdime · Jun 23, 2022

Confirmed that both 12V sockets in the dash (the one next to the gearbox and the one in front of the driver) are powered by the leisure battery and not the engine battery. The owner manual appears correct.

I've used this 12V-to-USBC-PD adapter (which works really well BTW) and plugged my 15'' MacBook Pro using a USB-C cable. Before plugging in my laptop, the leisure battery screen displayed a current of -1A. With the MacBook plugged in, it immediately increases to -5A to -8A. If I unplug the laptop, it goes back to -1A.

Looks like the received wisdom of "everything in front of the B pillar is powered by the engine battery" is no longer true in the T6.1. In fact, the only plugs powered by the engine battery in the whole van are the two USB-C plugs next to the gear box. Everything else is leisure battery.

That's good news. It means charging your laptop with a USB-C cable is easy even when the roof is down.

ardm17 · Jun 23, 2022

Mehdime said:
Confirmed that both 12V sockets in the dash (the one next to the gearbox and the one in front of the driver) are powered by the leisure battery and not the engine battery. The owner manual appears correct.

I've used this 12V-to-USBC-PD adapter (which works really well BTW) and plugged my 15'' MacBook Pro using a USB-C cable. Before plugging in my laptop, the leisure battery screen displayed a current of -1A. With the MacBook plugged in, it immediately increases to -5A to -8A. If I unplug the laptop, it goes back to -1A.

Looks like the received wisdom of "everything in front of the B pillar is powered by the engine battery" is no longer true in the T6.1. In fact, the only plugs powered by the engine battery in the whole van are the two USB-C plugs next to the gear box. Everything else is leisure battery.

That's good news. It means charging your laptop with a USB-C cable is easy even when the roof is down.

Useful info, many thanks.

Perhaps the old adage "If you can do then do, if you can't then teach and if you can't do either then write the manual" may not apply in this case ...

Gunslinger1976 · Mar 31, 2024

Mehdime said:
Hi,

The received wisdom on this forum is that everything ahead of the B pillar (I.e. everything in the cab) is powered by the engine battery (except for the inverter socket) and everything behind (I.e. in the camper area) is powered by the leisure batteries. Even California Chris states this in his video on the California electrics.

Yet, the manual of my T6.1 Ocean is very clear: *all* the 12V sockets are in fact powered by the leisure batteries. It explicitly lists them to avoid any confusion and both tm12V sockets in the dash are listed as being powered by the leisure batteries.

It makes sense to be honest because otherwise, there would be no accessible 12V socket to use to power e.g. a laptop when camping (the one underneath the back bench isn’t really accessible - no space to plug a USB-C PD adapter plus a USB-C cable).

So who is right? And how can we find out?

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Hi, an old thread I know but I just disconnected the starter battery to test this. I don’t have a cigarette charger adaptor so couldn’t check those sockets (top of dash and in the upper sleeping area) but the only other sockets which didn’t work were the 2 x USB-C by the cup holder on the front dash. This means the 230v socket on the side of the driver seat and all the sockets at the end of the units (USB and 230v) are powered by the leisure battery. Lastly, perhaps an obvious comment, but the powered side door could be opened at all from the outside but it could be manually opened from the inside.