Can't charge the leisure battery from the engine

K

kevin1000

Messages
13
Location
Sheffield
Vehicle
T7 ocean
I've just purchased an ex demo T7 Ocean Diesel and after the 2 hour drive home from the dealers I checked the battery levels and was suprised to see that the leisure battery was on 20%. I was expecting it to be full after such a long drive.

I've tried and EHU and it charges fine that way. I then went back to trying to charge it using the engine by starting the engine and checking the display. As the images show below, at first I got the expected behaviour, engine power was providing 30A and the leisure battery recieving 25A. But after a few seconds the engine power dropped to OA and the leisure battery quickly when back to -0.2A (the image shows 0.7A but I was abit quick with the camera!) . It would appear that I am unable to charge the leisure battery from the engine for longer than a few seconds.

Any suggestions? I'm new to the vehicle so could I be making a silly mistake somehow?

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13.3 v is fully charged with 25hours of estimated charge remaining! (edit: AGM bat)

What does the LB & starter show after 30 minutes with engine fully switch off and no load on the LB , I.e. nothing being used or plugged into 12v sockets
 
Last edited:
13.3 v is fully charged with 25hours of estimated charge remaining!

What does the LB & starter show after 30 minutes with engine fully switch off and no load on the LB , I.e. nothing being used or plugged into 12v sockets
Unfortunately since doing the last test I have had the vehicle on EHU. I'll take it off the EHU, take a picture, then leave for 30m, take another picture and report back! Thanks for the response.
 
13.3 v is fully charged with 25hours of estimated charge remaining!

What does the LB & starter show after 30 minutes with engine fully switch off and no load on the LB , I.e. nothing being used or plugged into 12v sockets
So the following 3 images are with the engine off, no load and no EHU. The first at 5:10pm, the second at 5:52pm and 3rd at 8:34pm. Does this information help explain why I cant charge the leisure battery from the engine? Thanks again for your help!


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So the following 3 images are with the engine off, no load and no EHU. The first at 5:10pm, the second at 5:52pm and 3rd at 8:34pm. Does this information help explain why I cant charge the leisure battery from the engine? Thanks again for your help!


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Both batteries are fully charged, so when you start the engine the Leisure battery will show an initial charging that rapidly drops to Zero as the electronics determine the Leisure batteries are fully charged.

Where did you get this 20% reading you mentioned in your original post?

The Hours calculation for the leisure batteries is based on a spot reading of the amps being drawn at that time and can vary a lot.
 
Both batteries are fully charged, so when you start the engine the Leisure battery will show an initial charging that rapidly drops to Zero as the electronics determine the Leisure batteries are fully charged.

Where did you get this 20% reading you mentioned in your original post?

The Hours calculation for the leisure batteries is based on a spot reading of the amps being drawn at that time and can vary a lot.
This is an image of the following day after I got home, you can see the leisure battery looks depleted from the image showing only 5h but I think from the Voltage looks like it’s charged (is that the case? I’m no expert!!!).

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I think the 20% came from the main screen that shows water levels and leisure battery charge, unfortunately I didn’t take a picture.

So it seems that the problem could be me relying on this spot calculation and the batteries were actually charged after my journey? Should I only rely on the voltage reading when determining if the batteries are charged?
 
This is an image of the following day after I got home, you can see the leisure battery looks depleted from the image showing only 5h but I think from the Voltage looks like it’s charged (is that the case? I’m no expert!!!).

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I think the 20% came from the main screen that shows water levels and leisure battery charge, unfortunately I didn’t take a picture.

So it seems that the problem could be me relying on this spot calculation and the batteries were actually charged after my journey? Should I only rely on the voltage reading when determining if the batteries are charged?
With Lithium batteries , unlike AGM, the voltage is almost maintained during use until it drops quickly as the batteries deplete.
When the picture was taken you had a current draw of 10.7 amps so the batteries would last for almost 6 hrs ie: you would draw 60 amps + during that time period if the current draw is maintained, BUT you have plugged in the EHU so you are now charging at 25 amps and using at 10.7 amps.
I would expect if you leave things as they are then the Mains charging amps would gradually decrease towards 10.7 amps and the Time remaining should increase as the batteries charge up. Normally switching the Ignition On/Of resets the Hours remaining calibration, but as long as you have a current draw of 10.7 amps I'm not sure if the Remaining Hours will increase that much. I'm not sure how sophisticated the calculation is when charging at the same time.
 
With Lithium batteries , unlike AGM, the voltage is almost maintained during use until it drops quickly as the batteries deplete.
When the picture was taken you had a current draw of 10.7 amps so the batteries would last for almost 6 hrs ie: you would draw 60 amps + during that time period if the current draw is maintained, BUT you have plugged in the EHU so you are now charging at 25 amps and using at 10.7 amps.
I would expect if you leave things as they are then the Mains charging amps would gradually decrease towards 10.7 amps and the Time remaining should increase as the batteries charge up. Normally switching the Ignition On/Of resets the Hours remaining calibration, but as long as you have a current draw of 10.7 amps I'm not sure if the Remaining Hours will increase that much. I'm not sure how sophisticated the calculation is when charging at the same time.
Thanks, that helps me better understand how things work. I think I need to drain the leisure battery and try again to see if the alternator charges it. I'm hopefully that perhaps there isnt an issue with the vehicle and its more my lack of experience in interpreting the battery display. I'll report back with findings. Thanks again for everyones help so far, much appreciated.
 
Thanks, that helps me better understand how things work. I think I need to drain the leisure battery and try again to see if the alternator charges it. I'm hopefully that perhaps there isnt an issue with the vehicle and its more my lack of experience in interpreting the battery display. I'll report back with findings. Thanks again for everyones help so far, much appreciated.
If the LB was / is full, before hook up, I would suspect you don't have an issue with alternator charging.

As you say , try using the LB to drop the Volts to approx 12.8v then start the vehicle, the LB should start to be charged at anywhere from 12.6v upto 15v (depends on revs) take the vehicle for a drive, you should notice the LB voltage increases to 14.4v (approximately) whilst it is receiving a charge from the alternator?
 
Thanks, that helps me better understand how things work. I think I need to drain the leisure battery and try again to see if the alternator charges it. I'm hopefully that perhaps there isnt an issue with the vehicle and its more my lack of experience in interpreting the battery display. I'll report back with findings. Thanks again for everyones help so far, much appreciated.
If the LB was / is full, before hook up, I would suspect you don't have an issue with alternator charging.

As you say , try using the LB to drop the Volts to approx 12.8v then start the vehicle, the LB should start to be charged at anywhere from 12.6v upto 15v (depends on revs) take the vehicle for a drive, you should notice the LB voltage increases to 14.4v (approximately) whilst it is receiving a charge from the alternator?
This is a chart of Capacity v Voltage of a 12v LiPo4 lithium battery as fitted in the New California.

IMG_2445.jpeg

Note the significant voltage change compared with the AGM leisure battery system fitted to the T4/5/5.1/6/6.1 Californias.

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I would be more concerned at the Amperage - what are you using in the van thats drawing 10.7A. ?
What's the 25 amp showing on the hookup that surely isn't what you are drawing?
 
Hi Kevin
I have had the same issue since the beginning of August after having no issues since the van was new in March. 2 trips to my local dealer (who had never seen the new Cali before) and software updates didn't remedy the problem. I took it to the nearest VW Camper Van specialist to me and the fix is a new control module. I've had to wait a couple of months for the part to come in and am booked in on the 17th/18th Feb. Will report back once it's done, hopefully with good news. I'm charging the battery via the EHU every couple of weeks in the mean-time to try and keep the battery healthy.
 
Hi Kevin
I have had the same issue since the beginning of August after having no issues since the van was new in March. 2 trips to my local dealer (who had never seen the new Cali before) and software updates didn't remedy the problem. I took it to the nearest VW Camper Van specialist to me and the fix is a new control module. I've had to wait a couple of months for the part to come in and am booked in on the 17th/18th Feb. Will report back once it's done, hopefully with good news. I'm charging the battery via the EHU every couple of weeks in the mean-time to try and keep the battery healthy.
Thanks for letting me know. I’d be really interested to hear if that resolves your problem, as it sounds very similar to my situation. To be clear, you can charge the vehicle battery with the alternator, just not the leisure battery?

I'm currently still doing some testing so I can clearly report the issue to the dealer.
 
Hi Kevin
Yes, main battery charges fine via the alternator but leisure battery doesn’t. The van is my daily driver. Leisure battery charges quickly via EHU but depletes gradually over 2-3 weeks. Good luck with the dealers. I found it a real battle initially for them to understand my issue. Dealer said it was either software or the control module and the software update didn’t fix it so they have ordered the latter. Some of my colleagues have suggested a relay issue but this has fallen on deaf ears with dealer and no doubt the new system is more complicated than previous models. Problem I have found is that it’s difficult to speak to the technicians directly.
 
Sounds like the same issue I had with my T6.1 Ocean - turned out to be a faulty relay in the split charge system. The alternator charging would start for a few seconds then cut out just like yours. Worth checking if your dealer can test the charging relays before going straight to a new control module.
 
Hi Kevin
Yes, main battery charges fine via the alternator but leisure battery doesn’t. The van is my daily driver. Leisure battery charges quickly via EHU but depletes gradually over 2-3 weeks. Good luck with the dealers. I found it a real battle initially for them to understand my issue. Dealer said it was either software or the control module and the software update didn’t fix it so they have ordered the latter. Some of my colleagues have suggested a relay issue but this has fallen on deaf ears with dealer and no doubt the new system is more complicated than previous models. Problem I have found is that it’s difficult to soak to the technicians directly
 
Hi Kevin
Yes, main battery charges fine via the alternator but leisure battery doesn’t. The van is my daily driver. Leisure battery charges quickly via EHU but depletes gradually over 2-3 weeks. Good luck with the dealers. I found it a real battle initially for them to understand my issue. Dealer said it was either software or the control module and the software update didn’t fix it so they have ordered the latter. Some of my colleagues have suggested a relay issue but this has fallen on deaf ears with dealer and no doubt the new system is more complicated than previous models. Problem I have found is that it’s difficult to soak to the technicians directly
Thanks, think I'm now convinced the van has an issue and I'm going to head to the dealers. PLease let me know how you get on and if the dealers resolve the issue for you!

Below is my latest testing of the problem. I'm posting so people can tell me I've tested it wrong or if I have it correct, so people can recognise the issue in their van.

The images below show the issue.

Image 1: Indicates the state of the batteries before attempting to charge them. Note, leisure battery on 20%
Image 2: Engine started, both batteries seem to be charging. Energy from the engine is ACTIVE.
Image 3: Within 60 seconds, energy from the engine switches to READY, leisure battery no longer charging but the vehicle battery continues to charge.


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Thanks, think I'm now convinced the van has an issue and I'm going to head to the dealers. PLease let me know how you get on and if the dealers resolve the issue for you!

Below is my latest testing of the problem. I'm posting so people can tell me I've tested it wrong or if I have it correct, so people can recognise the issue in their van.

The images below show the issue.

Image 1: Indicates the state of the batteries before attempting to charge them. Note, leisure battery on 20%
Image 2: Engine started, both batteries seem to be charging. Energy from the engine is ACTIVE.
Image 3: Within 60 seconds, energy from the engine switches to READY, leisure battery no longer charging but the vehicle battery continues to charge.


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I can’t imagine a T7 is much different to the 6.1 in using a basic relay switch when running to feed alternator power to the starter and leisure at the same time. It ready does look like this is not working properly to my untrained eyes.
 
I've just purchased an ex demo T7 Ocean Diesel and after the 2 hour drive home from the dealers I checked the battery levels and was suprised to see that the leisure battery was on 20%. I was expecting it to be full after such a long drive.

I've tried and EHU and it charges fine that way. I then went back to trying to charge it using the engine by starting the engine and checking the display. As the images show below, at first I got the expected behaviour, engine power was providing 30A and the leisure battery recieving 25A. But after a few seconds the engine power dropped to OA and the leisure battery quickly when back to -0.2A (the image shows 0.7A but I was abit quick with the camera!) . It would appear that I am unable to charge the leisure battery from the engine for longer than a few seconds.

Any suggestions? I'm new to the vehicle so could I be making a silly mistake somehow?

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View attachment 143483
Mine happened the same; No clue at the dealer; always saying that was a software problem; every 14 days i nee d to EHU; I finally had to tell them what the problem is (got from a wassap chat) and on wednesday they will fix it, It is the "disyuntor" = circuit breaker; hope it is the end to a very long story!!!
 
Following this thread as we are having the same issue on a t7 ocean cali diesel. Will try the circuit breaker
 
I've just purchased an ex demo T7 Ocean Diesel and after the 2 hour drive home from the dealers I checked the battery levels and was suprised to see that the leisure battery was on 20%. I was expecting it to be full after such a long drive.

I've tried and EHU and it charges fine that way. I then went back to trying to charge it using the engine by starting the engine and checking the display. As the images show below, at first I got the expected behaviour, engine power was providing 30A and the leisure battery recieving 25A. But after a few seconds the engine power dropped to OA and the leisure battery quickly when back to -0.2A (the image shows 0.7A but I was abit quick with the camera!) . It would appear that I am unable to charge the leisure battery from the engine for longer than a few seconds.

Any suggestions? I'm new to the vehicle so could I be making a silly mistake somehow?

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Hi It’s a side note to your problem. I leave my fridge turned On 24/7 as I’m concerned about the leisure battery being constantly fully charged during the winter months. I do daily my T7 Coast, but it can sit for 24hrs without moving so the battery can drop down to 50% sometimes. It doesn’t help your problem, but that is definitely wrong what’s happening to your van
 
Following this thread as we are having the same issue on a t7 ocean cali diesel. Will try the circuit breaker
Sorry to hear so many others are having the same issue. I’d be interested to hear if anyone has actually managed to get it fixed through their dealer. How was the experience and how long did it take?

I reported the issue to my dealer within the first week of ownership, so I believe I still have the option to reject the vehicle under the Consumer Rights Act. I really don’t want to send it back, I like the van and I’d like to give them the opportunity to fix it. That said, I definitely don’t want six months of going back and forth to the dealers!!
 
Sorry to hear so many others are having the same issue. I’d be interested to hear if anyone has actually managed to get it fixed through their dealer. How was the experience and how long did it take?

I reported the issue to my dealer within the first week of ownership, so I believe I still have the option to reject the vehicle under the Consumer Rights Act. I really don’t want to send it back, I like the van and I’d like to give them the opportunity to fix it. That said, I definitely don’t want six months of going back and forth to the dealers!!
We've had the van since last year and hadnt noticed the battery drain until now feels as if the button at the front to charge whilst driving has stopped working. I watched a YouTube Video from cali Chris where you can download a free app to the dash computer so its easier to check the battery charge it basically turns the screen into the same one as in the back better to keep an eye on the percentage. Good luck too!
 
I haven't seen anywhere in this thread mentions of the Max Power button. That's what makes T7 charge leisure battery during driving. I always use it since it makes StartStop system go away :)
Didn't know what it is called but ours has stopped charging the leisure battery no idea why on our T7 ☹️
 
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