Thinking of installing an onboard battery maintainer for winter when the temp drops below -20C.

Have my eye on this: https://no.co/genius2d

Assuming that my 2014 L405 has two batteries, any reason why this wouldn't work if connected it to the jump posts under the bonnet?

Mines not an onboard, but I did put a permanent connector wired onto those terminals.

Details on this thread

Thanks. And would you know if both batteries are on the same system or if you are only conditioning one of the batteries?

I think that there's a voltage sensing relay connecting them, so at rest they would be disconnected, however at charging voltages, connected.

I'm not 100% sure on that, but as the posts are there for a booster start, I'm assuming they connect to the main starting battery which would be the most important to have fully charged. Again, I could be wrong.....

However, with a conditioner, I think initially it will only be recognising the charge level of one battery - so whilst it might charge both, it would only do so if the single battery it was connected to needed a charge.

https://www.fullfatrr.com/forum/images/smiles/icon_thumbs.gif

On board?

IMHO, I wouldn't do that.
Why? Well, what happens if there is an electrical problem and the device causes a fire in your lovely FFRR?

Much safer to have it in the garage, (assuming you have one), and run a cable to a convenient hidden socket in the car grille, a-la CTEK MX range.  V6 Vogue - “Less is More” - less to go wrong!

Reading the gumpf from Noco, it seems to have a lot of fire / safety features built in. Can't be any worse than my block heater.

Well, if it ain’t even in there, it’s 100% safe?
Anything other poses an increased risk?
So many companies source cheap internal components from China these days, and how are we to know what the supplier QA is like?
I’d rather my charger unit be screwed to a plasterboard wall in my garage, than be inside my FFRR full of flammable stuff. Humans always think it will never happen to them, always someone else.  V6 Vogue - “Less is More” - less to go wrong!

 V6 Vogue - “Less is More” - less to go wrong!