Disconnecting Battery For A Month - Issues?

Zagora

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T6 Pro
Earlier this year i left my T6 parked for three weeks whilst on holiday. The battery was as charged as it could be (I know they only charge to 80%) and there's no excessive drain.
I returned to find the battery completly flat, no central locking and not even a flicker of light from the dash. I now understand this to be an issue with euro6 diesels.

I'm planning to leave the van again this winter for between one and three months, unfortunatly where it's parked there is no option to have a trickle charger connected.
If the battery was disconnected for this amount of time would it be an issue? Would the battery retain its charge? Are there any issues when reconnecting after a long period?

It's frustrating having paid so much for a new van I'm facing this problem, my nineteen year old transit always started first time after two months!
 
Check the battery first and make sure its ok, there is a known issue with many 'moll' branded batteries that dealers are replacing under warranty
If the battery is ok then there has to be a drain there somewhere ?
Have you considered a small portable solar panel on the dash fed into cig socket to keep the engine batt charged ??
 
Sounds like a dodgy battery or parasitic drain. I’ve left mine for more than 3 weeks and it’s fired up no problem. I have a Varta battery though (previous issue with Moll battery)
 
As above.

Get the battery checked... Mol had issues.

If its left in daylight have a look over here for a dash solar panel.....

Mobile Solar Panels ? . . . - How I Did It -

Apart from all that . . . . There is no issue leaving the battery disconnected apart from the obvious, no alarm etc.
 
The solar charger might help if there's enough sun but in a British winter left for a month or more it's unlikely to help, i'll look into it for next summer...

I've had the van from new and it has a Varta bsttery. I took it to a VW dealer, they charged it, kept it overnight and checked for any drain. No fault was found, everything 'normal', whatever normal means!

A neighbour has a fleet of VW Caddy vans, all euro6 diesels, same problem, some have had flat batteries after three or four days.
A friend has an 18 plate Landrover Discovery, euro6 diesel, same issue with those. He's on a Landrover forum with many complaining of flat batteries.
I spoke to Absolut5 who have a good reputation here doing audio, electrical upgrades and carpet lining. They've had many vans with flst batteries sfter being left for five days....its a problem
As much as I love my van it's annoying, Euro 6 diesels just aren't fit for purpose.
 
My Euro5 T6 regularly goes 4 weeks or more without being driven, and always starts instantly.

If I know it’s going to be that long, I do fully charge the battery with a decent charger before leaving it.

Pete
 
Take a spare charged battery and jump leads and leave it in the back.
 
Increase battery size?

I fitted a 110ah Exide AGM in a T5.1.. .. under the bonnet.
 
My camper van sits unused for weeks on end, I have one of these I just plug into the cig lighter and chuck on the dashboard.
It seems to keep the vehicle battery topped up in summer but over the winter months it isn’t as good and it needs a proper charge monthly.
https://www.amazon.co.uk/ALLPOWERS-...VJC0A1AX22N9&refRID=YT725XB6VJC0A1AX22N9&th=1

Have a look at this 50W fold up version.

more power + a proper PWM charge controller (which your one doesnt have)

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New link on ebay for folding panels.

BlueFusion Portable Folding Solar Panel Charger 50W, 100W, 120W | eBay

screenshot_20190821-114451_ebay-jpg.49308


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might help you out over winter months?

though agreed, nothing beats a proper multi-stage charger over winter.
 
The solar charger might help if there's enough sun but in a British winter left for a month or more it's unlikely to help, i'll look into it for next summer...

I've had the van from new and it has a Varta bsttery. I took it to a VW dealer, they charged it, kept it overnight and checked for any drain. No fault was found, everything 'normal', whatever normal means!

A neighbour has a fleet of VW Caddy vans, all euro6 diesels, same problem, some have had flat batteries after three or four days.
A friend has an 18 plate Landrover Discovery, euro6 diesel, same issue with those. He's on a Landrover forum with many complaining of flat batteries.
I spoke to Absolut5 who have a good reputation here doing audio, electrical upgrades and carpet lining. They've had many vans with flst batteries sfter being left for five days....its a problem
As much as I love my van it's annoying, Euro 6 diesels just aren't fit for purpose.


I think i agree . . . the battery should last for 4weeks . . . .But.

The Euro6 spec on most makes & models of car and vans use "stop/start" and "regen breaking" which as we know means the starter battery is only ever 80% full . . . .

add short hop journeys into the mix and you have a even lower battery. During winter . . . . . even worse.

When the van sleeps the spec is below 50mA draw but averages at between 25mA and 35mA for the alarm system to listen for a remote signal and also power the ultrasonics etc......

I've even tried maxing out the battery on a mains charger to 100% . . . . but as soon as you start driving the energy management system will soon have that battery straight back down to 80% before it start putting and charge back in . . .


so the solution?

get the battery tested by a third party?

get a dc clamp-meter and meter-out the rest & sleep current of the van to look for any parasitic draws

reduce the current draw , , , possibly disable the alarm? - also dont forget the 12v socket and OBD port are live all the time, so anything pullged in will draw power.

also what about anything hardwired that draws power? - - dash cams etc.

another option is to fit a larger capacity battery, that has more run time . . . .

another option is to try and use solar or EHU in some way to keep the battery topped up.

another option is to just carry around a small Lithium jump-back so you can self-start if the battery did go flat.
 
Earlier this year i left my T6 parked for three weeks whilst on holiday. The battery was as charged as it could be (I know they only charge to 80%) and there's no excessive drain.
I returned to find the battery completly flat, no central locking and not even a flicker of light from the dash. I now understand this to be an issue with euro6 diesels.

I'm planning to leave the van again this winter for between one and three months, unfortunatly where it's parked there is no option to have a trickle charger connected.
If the battery was disconnected for this amount of time would it be an issue? Would the battery retain its charge? Are there any issues when reconnecting after a long period?

It's frustrating having paid so much for a new van I'm facing this problem, my nineteen year old transit always started first time after two months!

If you disconnect the battery you won’t have an alarm which will almost certainly be a big issue with your vans insurance company
 
My euro 6 van gets left for weeks at a time without being driven, and has always fired up instantly, AND I do a fair few short journeys during its normal usage.
 
Parked in my garage (safelock engaged but alarms off) my vehicle battery looses 2% per day.

However take it out on a camping trip and it’s all over the place, with large losses. Currently, 4 days into a trip and it has dropped from 100% to 60% despite 300 miles travelled. We take care to minimise draw on the vehicle battery but as soon as you just open a door I presume it springs into action stations.
 
It’s easier in a camper with a solar panel and leisure battery, then you can just trickle extra solar power into the starter.

The NDS system installed in our camper isn’t configured to do that. Their relevant manual appears to show their equipment will not directly support this for ‘smart alternator Euro 6’ setups.

Can something be retrofitted on top of an existing system, or can the 12V leisure output somehow be connected to the vehicle 12V socket?
 
The NDS system installed in our camper isn’t configured to do that. Their relevant manual appears to show their equipment will not directly support this for ‘smart alternator Euro 6’ setups.

Can something be retrofitted on top of an existing system, or can the 12V leisure output somehow be connected to the vehicle 12V socket?

Yes, if your solar controller doesn’t have that facility you can just use a “Battery Master” style separate box - they’re pretty reasonably priced.
 
It’s easier in a camper with a solar panel and leisure battery, then you can just trickle extra solar power into the starter.
This is exactly what I do, I have a photonic universe semi flexible 150w solar panel supplying a 110ah AGM leisure battery via a victron blue solar mppt 75/15 controller with a votronic 2a 12v DC to DC battery to battery trickle charger connected to the starter battery via the load output on the solar controller, the system works perfectly for me keeping both batteries charged.
 
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