Leisure batteries not charging on EHU or from alternator only from solar -T6.1

Virg · Jul 29, 2024

Hi

I had my water pump replaced recently by VW and the following weekend was away and on hook up. Despite driving about 60 miles and being on hookup all weekend the leisure batteries had fully discharged by the time I got home. The fridge had been on most of the weekend. The hook up was working.

The van went back in to VW they checked it and said it was fine.

Went away again the weekend and had the same problem. Here is a bit more detail and a photo.

The van has driven about 100 miles and on arrival had >60 hrs of charge in the leisure battery
It was on hook up and the hook up was working (ie using kettles etc so not a breaker issue)
The fridge was on at 4 so drawing from the leisure battery after 12 hours on hook up and with the fridge on the leisure battery was showing only >33 hours so is draining (see photo)
By the end of the weekend the battery had drained to only 5 hours despite being on hook up
The solar panels (2x100W) are charging the leisure batteries

Thanks all for any input.

WelshGas · Jul 29, 2024

Virg said:
Hi

I had my water pump replaced recently by VW and the following weekend was away and on hook up. Despite driving about 60 miles and being on hookup all weekend the leisure batteries had fully discharged by the time I got home. The fridge had been on most of the weekend. The hook up was working.

The van went back in to VW they checked it and said it was fine.

Went away again the weekend and had the same problem. Here is a bit more detail and a photo.

The van has driven about 100 miles and on arrival had >60 hrs of charge in the leisure battery
It was on hook up and the hook up was working (ie using kettles etc so not a breaker issue)
The fridge was on at 4 so drawing from the leisure battery after 12 hours on hook up and with the fridge on the leisure battery was showing only >33 hours so is draining (see photo)
By the end of the weekend the battery had drained to only 5 hours despite being on hook up
The solar panels (2x100W) are charging the leisure batteries

Thanks all for any input.
F
View attachment 127018

Firstly, the Hours remaining is a fairly inaccurate calculation based on spot data of power
consumption. The voltage is accurate. That picture shows you are on EHU and float charge.
Who installed the solar panels? Is the negative from the Solar control unit connected to a chassis ground point, normally the rear leisure battery clamp bolt on the T6.1?
If the black -tve solar lead is connected to the rear leisure battery-tve pole it can upset the Control Panel calculations.
One other thing to check is the 75/100 amp cube fuse on the +tve pole of rear leisure battery. They are fragile and if it blows the vehicle is running on 1 leisure battery BUT the rear battery may be charged by solar but not connected to vehicle electrics.

Virg · Jul 29, 2024

Thank you very much for this.

I think what you are saying is that the problem may be coming from the solar and that the leisure batteries are still charging from the EHU and when driving from the alternator.

Coils the replacement of the water pump have upset something?

The solar panels were from solar camper solutions and fitted to their instructions but not by them.

I am about to take the van back in to be but from what you are saying it may not be their issue but mine (ie solar panels)

WelshGas · Jul 29, 2024

Virg said:
Thank you very much for this.

I think what you are saying is that the problem may be coming from the solar and that the leisure batteries are still charging from the EHU and when driving from the alternator.

Coils the replacement of the water pump have upset something?

The solar panels were from solar camper solutions and fitted to their instructions but not by them.

I am about to take the van back in to be but from what you are saying it may not be their issue but mine (ie solar panels)

Check the rear leisure battery , panel base of rear wardrobe. Thin black wire from solar panel control should be connected to battery clamp bolt.

Virg · Aug 3, 2024

WelshGas said:
Firstly, the Hours remaining is a fairly inaccurate calculation based on spot data of power
consumption. The voltage is accurate. That picture shows you are on EHU and float charge.
Who installed the solar panels? Is the negative from the Solar control unit connected to a chassis ground point, normally the rear leisure battery clamp bolt on the T6.1?
If the black -tve solar lead is connected to the rear leisure battery-tve pole it can upset the Control Panel calculations.
One other thing to check is the 75/100 amp cube fuse on the +tve pole of rear leisure battery. They are fragile and if it blows the vehicle is running on 1 leisure battery BUT the rear battery may be charged by solar but not connected to vehicle electrics.

View attachment 127020

Thank you for your reply. I thought it might be useful to update you. Having been at VW for the last week the problem has been resolved. I understand that they performed a software update on the control panel which has sorted the problem.

Virg · Aug 13, 2024

Further update! Unfortunately not fixed.

I can confirm that the problem is with the control panel but the update has not fixed it.

Despite being on EHU/driving and solar panels topping up the leisure batteries (which are full) the control panel hours remaining shows the battery charge incorrectly reducing (when there is a load like fridge) to zero then shows battery flat at which point the control panel goes blank and the fridge and water pump go off. Control for the Poptop is also lost.
In addition the control panel is also wrongly showing the water tank as being full when it’s empty.

The only way of reactivating the control panel is to have the engine running which allows the Poptop to be raised/lowered and the fridge and water pump to work. As soon as the engine is turned off the screen goes balm again with only “battery flat” showing (and EHU symbol if on hookup)

The van is going back in to VW!!