A question about flat leisure batteries

icic · Jan 21, 2024

I haven't used our van for a couple of months and found the batteries completely flat. We have solar panels but the fridge was left on. I've been for long drive and still no power whatsoever in the batteries. I believe I need to charge them 48 hours from the mains to try to revive them. However, I live in a terrace house so won't be able to have a cable running out to the van for 48 hours. It would more likely to be spells of time during the daytime (say 8 hours at a time) I have a few questions, running a charge less than 48 hours driving the van then charging again straight away would that work to charge the batteries or is that not going to be effective? Does it have to be 48 hours continuously and if I only part charge them would that damage them further ? I have to drive 3 hours tomorrow and stay in the van overnight (on mains ) but then would need to drive the van again next day (would that damage the batteries further) any advise on how to get my batteries to like would be great

WelshGas · Jan 21, 2024

icic said:
I haven't used our van for a couple of months and found the batteries completely flat. We have solar panels but the fridge was left on. I've been for long drive and still no power whatsoever in the batteries. I believe I need to charge them 48 hours from the mains to try to revive them. However, I live in a terrace house so won't be able to have a cable running out to the van for 48 hours. It would more likely to be spells of time during the daytime (say 8 hours at a time) I have a few questions, running a charge less than 48 hours driving the van then charging again straight away would that work to charge the batteries or is that not going to be effective? Does it have to be 48 hours continuously and if I only part charge them would that damage them further ? I have to drive 3 hours tomorrow and stay in the van overnight (on mains ) but then would need to drive the van again next day (would that damage the batteries further) any advise on how to get my batteries to like would be great

You are very unlikely to do any additional damage. But if you want the best chance of recovering the Leisure Batteries then I would suggest removing both batteries and charge them individually using a smart charger such as a ctek 10 that can condition a battery .

icic · Jan 21, 2024

Thank you I will get a Ctek 10, if I remove them individually can I still use mains power in the van with one or no batteries, as I need to stay in it for a night while they are mains charing in the house?

Also I presume I have to take out the seat to get to the battery, it that easy I found this guide https://vwcaliforniaclub.com/thread...arger-to-replace-vw-split-charge-relay.23466/

If I do this how do I Make sure the air bag does not go off not clear from the link
Thanks so much

WelshGas · Jan 21, 2024

icic said:
Thank you I will get a Ctek 10, if I remove them individually can I still use mains power in the van with one or no batteries, as I need to stay in it for a night while they are mains charing in the house?

Also I presume I have to take out the seat to get to the battery, it that easy I found this guide https://vwcaliforniaclub.com/thread...arger-to-replace-vw-split-charge-relay.23466/

If I do this how do I Make sure the air bag does not go off not clear from the link
Thanks so much

As long as you have 1 battery connected that’s fine.
The front battery under the chair.
Switch Off Ignition. This will disable air bags. DO NOT switch on the ignition until the electrical connections under the chair have been remade. NB: you may not need to disconnect them. Unbolt seat and lean it forward against Dashboard. I found there was sufficient room to remove battery without disconnecting the plugs.

icic · Jan 21, 2024

Thank you so much for your advice

Ch1pbutty · Jan 22, 2024

Can you not leave the batteries in situ, and charge via one of the leisure 12v sockets using the Ctek?

CTEK Comfort Connect - Cigarette Plug

The CTEK Comfort Connect - 12v/Cigarette Power Plug Adaptor is an easy to fit adapter that allows charging through the 12v cigarette lighter or 12v power accessory socket from a CTEK compatible charger.Compatible with all CTEK chargers up to 10 A.400mm cable.To allow operation, the socket must...

www.demon-tweeks.com

icic · Jan 22, 2024

can you explain more I don’t understand, how would that charge the flat battery, can you charge through a 12 volt socket like the one by the door under the passenger seat ?

Ch1pbutty · Jan 22, 2024

icic said:
can you explain more I don’t understand, how would that charge the flat battery, can you charge through a 12 volt socket like the one by the door under the passenger seat ?

You can charge via the 12v socket using the adaptor. We used to do it with our Beach before we had solar panels fitted. One of the dash sockets was leisure, the other was engine battery.

The only thing it won't do is tell you which one of your 2 leisure batteries is in bad health (if any). They might both be fine after a charge as the I understand that Oceans indicator is not always entirely accurate.

Might be worth trying with the lead before you take the batteries out.

WelshGas · Jan 22, 2024

Ch1pbutty said:
You can charge via the 12v socket using the adaptor. We used to do it with our Beach before we had solar panels fitted. One of the dash sockets was leisure, the other was engine battery.

The only thing it won't do is tell you which one of your 2 leisure batteries is in bad health (if any). They might both be fine after a charge as the I understand that Oceans indicator is not always entirely accurate.

Might be worth trying with the lead before you take the batteries out.

The OP stated he lived in a terrace house so unable to plug into the mains supply at home.
Your method could work but requires a Mains supply.

icic · Jan 22, 2024

So with the CTEC how long do you need to charge the batteries for ? is it still 48 hours and does charging via socket or direct to battery terminal make any difference to time

icic · Jan 22, 2024

so 48 hours whatever the method

WelshGas · Jan 22, 2024

icic said:
so 48 hours whatever the method

The cTek has a series of LEDs that light up as each stage of the charging profile is completed so each battery needs to complete the cycle.

andyinluton · Jan 22, 2024

icic said:
Thank you I will get a Ctek 10, if I remove them individually can I still use mains power in the van with one or no batteries, as I need to stay in it for a night while they are mains charing in the house?

Sorry if I am stating the obvious but just be careful with the leads that you have taken off the battery that you removed, the end of the positive one will still be live with the power coming from the battery thats still in place.

Skootyalan · Jan 26, 2024

Hi, I have had a similar problems hamsters couple of weeks in Panama. I tried leaving van plugged in for a number of days. While engine battery fine the leisure batteries were seen as low/ empty by the van. So, I stuck a Ctek on each battery for over 24 hours. I think batteries had charge but the van didn’t agree. I took the van to VW van centre in Hull for diagnostic which they told me needed a software reset. The van was fine when I collected and as behaved since. So, I wonder if the van electronics get confused when the leisure batteries run down? I was worried the batteries had been destroyed by running flat, but they are fine. I suspect my problem was caused by the dashcam being on while I was away.