Leisure battery unknown drain

WolfieRose

New Member
Hi, really needing some help with my new camper.
I recently bought a T6 all kitted out. Everything seemed to work ok to begin with in the first month. I took it away on a weekend trip and noticed the battery was not charged so I had to go to a site and hook up to get electricity.
After leaving the site I turned all power off at the control panel expecting the charge to stay but within a short period of time the battery had drained again. I took it to a garage, they checked the battery and said it was at 6% and i needed a new leisure battery. Which they replaced for me. I went away and tried charging the new battery to full capacity but it was not fully charging. I asked an auto electrician to check the new battery, he turned on the power at the control panel and the battery drained within about 20 minutes completely. I was told by the auto electrician that I needed to get a new split charge relay (I currently have a VSR) he recommended I upgrade to a DC to DC converter instead.
Has anyone else come across this before? I am worried that changing the split charge relay may not fix this issue with the battery drain, considering it went down so quickly on a new battery.

Any help or guidance appreciated, I can provide more info if needed.

Thanks in advance.

From the Transporter newbie - keen to learn :)
 
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Welcome to the forum and T6 life. I’d recommend posting pictures of your leisure battery (showing type, capacity and both connectors), your control panel (and other switches etc), other electrical boxes/chargers, your VSR and also your starter battery (details as leisure battery) as that will help us diagnose the issue. At the moment it could be one of many possibilities depending on your setup. The fact the battery didn’t charge on the drive there is an issue to start with.
 
Hi, thank you for such a prompt reply, I will get some photos and will start adding them in asap. I’m not sure where I would find the VSR, it was only because the auto electrician said it had died that I even knew I had one. I will come back with more info soon. Thank you so much IMG_9716.jpeg
 
Is it a new conversion? Is it under warranty?

Looks like a Sargent system, maybe the relay is integrated into that?
 
Is it a new conversion? Is it under warranty?

Looks like a Sargent system, maybe the relay is integrated into that?
It was a conversion done in Germany apparently (hence the name Wolfie) I think this was a few years ago from what the previous owner told me
 
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There is a lot going on there, some of which may be causing your issue and some of which will/could cause other problems.

First, the 2 white cables attached to the SB negative should not be there, they should be attached to a chassis ground point. The little box on the main negative cable is the vehicle ‘shunt’ which tells the ECU what is happening to the SB. Anything attached to the battery side of the shunt bypasses it meaning the ECU is getting false readings. That will cause odd charging and maybe unwanted drain on the SB.

Second - a VSR is not suitable for a T6 as it is fitted with a smart alternator. In short this varies the charge from the alternator (to increase economy) and only charges the SB to 80% to leave capacity for charging while braking. This means the LB will only charge to about 80% and gets wildly varying charge voltages. Changing the VSR for a DC to DC charger will mean proper charging of your LB (and an upgrade paths for lithium in the future). It may well be an easy swap using existing cables. You may find this solves your problem entirely.

Third - try and identify what all the cables and fuses are off you SB pos. It’s unusual to have so many and they may not be helping. Do you have a towbar with electric ls? Extra spot/fog lights etc?

This thread gives a lot of info about swapping a VSR for DC-DC (plus other upgrades) - Power Upgrade Advice
 
There is a lot going on there, some of which may be causing your issue and some of which will/could cause other problems.

First, the 2 white cables attached to the SB negative should not be there, they should be attached to a chassis ground point. The little box on the main negative cable is the vehicle ‘shunt’ which tells the ECU what is happening to the SB. Anything attached to the battery side of the shunt bypasses it meaning the ECU is getting false readings. That will cause odd charging and maybe unwanted drain on the SB.

Second - a VSR is not suitable for a T6 as it is fitted with a smart alternator. In short this varies the charge from the alternator (to increase economy) and only charges the SB to 80% to leave capacity for charging while braking. This means the LB will only charge to about 80% and gets wildly varying charge voltages. Changing the VSR for a DC to DC charger will mean proper charging of your LB (and an upgrade paths for lithium in the future). It may well be an easy swap using existing cables. You may find this solves your problem entirely.

Third - try and identify what all the cables and fuses are off you SB pos. It’s unusual to have so many and they may not be helping. Do you have a towbar with electric ls? Extra spot/fog lights etc?

This thread gives a lot of info about swapping a VSR for DC-DC (plus other upgrades) - Power Upgrade Advice
Some amazing guidance here, I can’t thank you enough already. There have been multiple mechanics playing with the SB recently, and I have no idea what they have touched or moved or how they have left it. One of them told me I needed a new SB, the other 2 said it was fine. I am having alot of conflicting information. But from what you say above, it makes sense in why the problems are happening as they are.

I have the van booked in next week (earliest appointment I could get with auto electrician) to change the VSR to DC to DC charger to see if this is what the issue could be. He said my current VSR is not working. He is going to apply a Victron DC to DC, from what I see online, this looks like a good option I hear?
I’m going away this evening with my daughter for the wkd, so I charged the new LB last night and disconnected so it doesn’t drain it. I had been running around in the van this morning and When I got home this afternoon I noticed the LB had drained…from what the control panel said anyway.

I wasn’t sure the LB could drain when it was disconnected, but, I don’t know enough about it, just from what I have been told from others.

I am so confused
 
Some amazing guidance here, I can’t thank you enough already. There have been multiple mechanics playing with the SB recently, and I have no idea what they have touched or moved or how they have left it. One of them told me I needed a new SB, the other 2 said it was fine. I am having alot of conflicting information. But from what you say above, it makes sense in why the problems are happening as they are.

I have the van booked in next week (earliest appointment I could get with auto electrician) to change the VSR to DC to DC charger to see if this is what the issue could be. He said my current VSR is not working. He is going to apply a Victron DC to DC, from what I see online, this looks like a good option I hear?
I’m going away this evening with my daughter for the wkd, so I charged the new LB last night and disconnected so it doesn’t drain it. I had been running around in the van this morning and When I got home this afternoon I noticed the LB had drained…from what the control panel said anyway.

I wasn’t sure the LB could drain when it was disconnected, but, I don’t know enough about it, just from what I have been told from others.

I am so confused
Just to add the auto electrician said he is going to sort out the fuses next week for me too and tidy it all up because he said the fuses are all over the place, this will probably make more sense to you then to me
 
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No problem, that’s what the forum is all about. Victron is very good and you will be able to monitor it with your phone. I wouldn’t rush into new batteries until your issue is resolved and you know what the state of play is. I just hope your electrician knows what they are doing as the state of many so called ‘professional’ leisure electric installs (mine included) takes a lot to be desired. If you are even slightly handy then this is something you could look at yourself with support from here. It’s not complicated, just a different language, and a bit of simple logic to get things sorted. I’m no electrician or trade but with a bit of research have changed the entire leisure system in my van. If I can do it so can anyone!
 
No problem, that’s what the forum is all about. Victron is very good and you will be able to monitor it with your phone. I wouldn’t rush into new batteries until your issue is resolved and you know what the state of play is. I just hope your electrician knows what they are doing as the state of many so called ‘professional’ leisure electric installs (mine included) takes a lot to be desired. If you are even slightly handy then this is something you could look at yourself with support from here. It’s not complicated, just a different language, and a bit of simple logic to get things sorted. I’m no electrician or trade but with a bit of research have changed the entire leisure system in my van. If I can do it so can anyone!
I will be holding off on getting any new batteries at the moment. Fortunately since I have had the sensor done on the rear wheel, the ABS and the start stop is now working again. It is just the internal electrics to deal with now. I noticed when I was away in it at the weekend that I do have a Sargent set up.
I also charged up the LB before I went, disconnected the LB and it still drained. I will get the victron installed and see what happens after that, if no joy, I will be back with more questions if that’s ok;)
 
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