Leisure batteries WARNING

[Geesvw]

When replacing both your leisure batteries, make sure that the live terminal on the second battery is isolated (not touching the chassis), if you forget to check, you could have major electrical problems. Put the front battery in first (under the passenger seat), followed by the rear
In my case I didn't check, and now have a £7500 insurance claim, involving a new leisure loom which is having to be manufactured at VW headquarters in Germany. This is on a 2008 Cali and they aren't available from stock!

 

[WelshGas]

Sorry to hear that. Yes, a lot of current for a direct short circuit.
There is a 50 or 75amp cube fuse on the Rear battery + tve pole, or at least there should be.......
This would protect the circuit if replacing the front battery and you get a short circuit, but nothing on the front battery if the rear battery + tve short circuits.

I've been toying with the idea of a cube fuse on the front battery or if there is no vertical room an in-line fuse.

 

[Geesvw]

Sorry to hear that. Yes, a lot of current for a direct short circuit.
There is a 50 or 75amp cube fuse on the Rear battery + tve pole, or at least there should be.......
This would protect the circuit if replacing the front battery and you get a short circuit, but nothing on the front battery if the rear battery + tve short circuits.

I've been toying with the idea of a cube fuse on the front battery or if there is no vertical room an in-line fuse.

Yes I upgraded to 75amp cube fuse when having a diesel heater problem, it did do the trick until the batteries finally died

 

[Loz]

That's why you should disconnect the negative of both batteries first...

 

[Geesvw]

That's why you should disconnect the negative of both batteries first...

The sad thing is I've removed and replaced two previous sets of batteries in the past! I do know how to remove both batteries, but forgot on the last occasion

 

[rod_vw]

When replacing both your leisure batteries, make sure that the live terminal on the second battery is isolated (not touching the chassis), if you forget to check, you could have major electrical problems. Put the front battery in first (under the passenger seat), followed by the rear
In my case I didn't check, and now have a £7500 insurance claim, involving a new leisure loom which is having to be manufactured at VW headquarters in Germany. This is on a 2008 Cali and they aren't available from stock!

My first port of call in your situation would have been Martyn from https://www.travelvolts.net/ . Martyn has more knowledge of VW Camper electrics than any VW dealership you will find. I guess he can make up a new loom if necessary or repair the existing one if it's possible.
Personally I would have delved into the repair myself but there again I have built five of my own campers.

Re the leisure battery fusing, I fit separate fuses in the +ve cable to each battery and a notice by both warning of the peril that you have found.

Rod

 

[Hannick]

Would having both RCD’s turned to “off” make any difference to this happening?

 

[WelshGas]

Would having both RCD’s turned to “off” make any difference to this happening?

No. Only works on Mains supply.

 

[Hannick]

OK. I changed both my leisure batteries today and all went well.

But I show this photo of the rear compartment while I changed the rear battery over (I did the front seat one first) as having now read this thread I am wondering if I had a lucky escape with the +ve lead lying on the floor.

 

[Geesvw]

OK. I changed both my leisure batteries today and all went well.

But I show this photo of the rear compartment while I changed the rear battery over (I did the front seat one first) as having now read this thread I am wondering if I had a lucky escape with the +ve lead lying on the floor.

View attachment 30080

I think the floor is made of the same aluminium composite that the rest of the wardrobe and other compartments are made of, if you've ever cut it open its a layer of aluminium bonded between two outer layers, which would be the insulation element.

 

[Hannick]

So the main danger is when you change the front battery as there is a lot of metal under there to cause a short.

 

[Loz]

So the main danger is when you change the front battery as there is a lot of metal under there to cause a short.

That is why you should remove both negative leads before you start.