California battery issues - workaround

[Stu65]

Hi all,

There have been a number of posts raising concerns about leisure battery/charging issues, including the following:

1. When setting off, the van displays a “Cable connected” warning on the dash, despite the charging cable having clearly been unplugged.
2. The leisure batteries do not charge while driving, even after pressing the “Boost” button.
3. The leisure batteries no longer charge when the van is connected to an electrical hook-up (EHU).

please note, my Cali Ocean supposedly had the fix applied and was fine for a couple of months. My issues started after I plugged the van in at home to ensure the leisure batteries were at 100% before setting off for a long weekend.

My suspicion is that something in the charging/control system has become confused and is effectively reversing the signals it is receiving. If the system thinks the van is still connected to the mains when driving, it prevents charging from the alternator. Conversely, when connected to the EHU, it appears to think the van is unplugged and therefore doesn't initiate charging from the hook-up.

I came across a post from swabes, who had resolved the same issue by removing the 25A fuses from the fuse board above the leisure batteries and from the fuse board under the bonnet, leaving them out for a few minutes and then replacing them.

I tried this myself and, sure enough, it resolved all of my issues:

• The batteries charged from the EHU.
• They charged normally while driving.
• The “Cable connected” error disappeared.
• We had a successful weekend away using the site hook-up with no further errors.
• Everything worked as expected.
• On the journey home, the leisure batteries were back at 100%.

So, whatever is happening, removing the fuses appears to completely reset the relevant charging/control system.

I had the van booked into my dealer for diagnostics, so I contacted them to cancel the appointment as there was nothing left for them to investigate. I did, however, ask if they could provide a fuse diagram, as I'd like to understand exactly which systems are being powered down when these fuses are removed.

Unfortunately, they declined and simply pointed me towards the owner's manual. I may be missing something, but the information in the manual regarding the fuses amounts to little more than a single paragraph and doesn't provide the level of detail I was looking for.

Does anyone have a detailed fuse diagram for the T7 Multivan, particularly identifying the 25A fuses associated with the leisure battery/charging system?

I've searched online, but most of the information I can find relates to the T6.1, rather than the T7 Multivan. I'd really like to understand exactly what I'm powering down when carrying out this reset.

Finally, a big thank you to Swabes for posting the workaround in the first place. Until VW comes up with a proper fix, at least this gives me a way of resetting the system if the problem occurs again — and hopefully it may help others experiencing the same symptoms.

 

[Toneb]

"Does anyone have a detailed fuse diagram for the T7 Multivan"

 

[Chriskend]

Cracking job, my t7 ocean has been perfect but i have been keeping an eye on the above battery faults just in case i get the same issues in the future. Its typical of vw to hold back information that might effect their pockets. Working in IT for the last 30 years and a fare chunk for Microsoft, the first port of call of any diagnostics is to switch it off and on (the so called finger of destiny). Most of the time (if not all) it cures the issue. All new vehicles are now just computers on wheels so why shouldn’t the same apply to them. The wife and i both run tesla’s and they have a hard reset built in. ( used it once or twice) so why shouldn’t others. Well done on posting this fix, it will help a fair few t7 owners out of a jam.

 

[swabes]

Cracking job, my t7 ocean has been perfect but i have been keeping an eye on the above battery faults just in case i get the same issues in the future. Its typical of vw to hold back information that might effect their pockets. Working in IT for the last 30 years and a fare chunk for Microsoft, the first port of call of any diagnostics is to switch it off and on (the so called finger of destiny). Most of the time (if not all) it cures the issue. All new vehicles are now just computers on wheels so why shouldn’t the same apply to them. The wife and i both run tesla’s and they have a hard reset built in. ( used it once or twice) so why shouldn’t others. Well done on posting this fix, it will help a fair few t7 owners out of a jam.

Hahahaha - I worked at Microsoft for 13 years!

 

[swabes]

I found this when I had the probelm as I was curious like yourself. Its for the multivan so doesnt include the campervan specific unit though:
https://fuse-box.info/volkswagen/volkswagen-multivan-t7-2022-2024-fuses-and-relays#google_vignette

 

[Stu65]

"Does anyone have a detailed fuse diagram for the T7 Multivan"

Thanks, I should have finished that sentence with Ocean campervan as I suspect the reset came about pulling the fuses above the leisure batteries, what you have share is still of value

 

[Stu65]

Cracking job, my t7 ocean has been perfect but i have been keeping an eye on the above battery faults just in case i get the same issues in the future. Its typical of vw to hold back information that might effect their pockets. Working in IT for the last 30 years and a fare chunk for Microsoft, the first port of call of any diagnostics is to switch it off and on (the so called finger of destiny). Most of the time (if not all) it cures the issue. All new vehicles are now just computers on wheels so why shouldn’t the same apply to them. The wife and i both run tesla’s and they have a hard reset built in. ( used it once or twice) so why shouldn’t others. Well done on posting this fix, it will help a fair few t7 owners out of a jam.

I have worked in IT for the last 40+ years and like you have a Tesla so , on the odd occasion it needs a kick it can be done, need something similar in the California!

 

[Chriskend]

I have worked in IT for the last 40+ years and like you have a Tesla so , on the odd occasion it needs a kick it can be done, need something similar in the California!

I totally agree, if it wasn’t for forums like this then there would be a lot more head and arse scratching going on.

 

[Chriskend]

I see there is an issue in the childlock fault thread,,,,,, wouldn’t suprise me if there is a very similar fix

 

[Janneman]

Hi all,

There have been a number of posts raising concerns about leisure battery/charging issues, including the following:

1. When setting off, the van displays a “Cable connected” warning on the dash, despite the charging cable having clearly been unplugged.
2. The leisure batteries do not charge while driving, even after pressing the “Boost” button.
3. The leisure batteries no longer charge when the van is connected to an electrical hook-up (EHU).

please note, my Cali Ocean supposedly had the fix applied and was fine for a couple of months. My issues started after I plugged the van in at home to ensure the leisure batteries were at 100% before setting off for a long weekend.

My suspicion is that something in the charging/control system has become confused and is effectively reversing the signals it is receiving. If the system thinks the van is still connected to the mains when driving, it prevents charging from the alternator. Conversely, when connected to the EHU, it appears to think the van is unplugged and therefore doesn't initiate charging from the hook-up.

I came across a post from swabes, who had resolved the same issue by removing the 25A fuses from the fuse board above the leisure batteries and from the fuse board under the bonnet, leaving them out for a few minutes and then replacing them.

I tried this myself and, sure enough, it resolved all of my issues:

• The batteries charged from the EHU.
• They charged normally while driving.
• The “Cable connected” error disappeared.
• We had a successful weekend away using the site hook-up with no further errors.
• Everything worked as expected.
• On the journey home, the leisure batteries were back at 100%.

So, whatever is happening, removing the fuses appears to completely reset the relevant charging/control system.

I had the van booked into my dealer for diagnostics, so I contacted them to cancel the appointment as there was nothing left for them to investigate. I did, however, ask if they could provide a fuse diagram, as I'd like to understand exactly which systems are being powered down when these fuses are removed.

Unfortunately, they declined and simply pointed me towards the owner's manual. I may be missing something, but the information in the manual regarding the fuses amounts to little more than a single paragraph and doesn't provide the level of detail I was looking for.

Does anyone have a detailed fuse diagram for the T7 Multivan, particularly identifying the 25A fuses associated with the leisure battery/charging system?

I've searched online, but most of the information I can find relates to the T6.1, rather than the T7 Multivan. I'd really like to understand exactly what I'm powering down when carrying out this reset.

Finally, a big thank you to Swabes for posting the workaround in the first place. Until VW comes up with a proper fix, at least this gives me a way of resetting the system if the problem occurs again — and hopefully it may help others experiencing the same symptoms.

I wonder if such a 'reset' couldn't also be done by disconnecting the batteries for a few minutes? In that case, you wouldn't have to go searching for the relevant fuses.

 

[WelshGas]

Volkswagen does not print a fixed, definitive fuse layout in the vehicle handbook because layouts vary wildly depending on your exact model generation (T5, T6, T6.1, or T7 New Multivan), engine, and camper specifications (Beach, Coast, or Ocean ).

How to Obtain Your Exact Factory Diagram
If you are dealing with a newer model (like a T6.1 Ocean or T7 Multivan) and troubleshooting complex electrical faults, it is highly recommended to get the factory-exact blueprint:

1. Go to the official Volkswagen erWin Portal.
2. Register a flat-rate account (a 1-hour subscription costs around €7–€10).
3. Enter your vehicle's unique VIN (Vehicle Identification Number).
4. Download the complete, official "Fuses and Relay Locations" PDF, which is tailored exactly to how your specific van left the factory.

 

[Stu65]

I wonder if such a 'reset' couldn't also be done by disconnecting the batteries for a few minutes? In that case, you wouldn't have to go searching for the relevant fuses.

I did look at this initially, unfortunately the vehicle 12v battery is under the passenger seat and by the looks of it you need to remove the seat to get to it...easier to pull the fuses!

 

[Stu65]

Volkswagen does not print a fixed, definitive fuse layout in the vehicle handbook because layouts vary wildly depending on your exact model generation (T5, T6, T6.1, or T7 New Multivan), engine, and camper specifications (Beach, Coast, or Ocean ).

How to Obtain Your Exact Factory Diagram
If you are dealing with a newer model (like a T6.1 Ocean or T7 Multivan) and troubleshooting complex electrical faults, it is highly recommended to get the factory-exact blueprint:

1. Go to the official Volkswagen erWin Portal.
2. Register a flat-rate account (a 1-hour subscription costs around €7–€10).
3. Enter your vehicle's unique VIN (Vehicle Identification Number).
4. Download the complete, official "Fuses and Relay Locations" PDF, which is tailored exactly to how your specific van left the factory.

Many thanks for the recommendation, I will look into that

 

[Tracy Paine]

Reading this as our new California T7 Coast ( 2025) is currently sitting in the garage having the battery software installed. The leisure battery was not holding charge. Having loved our T5 Cali for 9 years and never having a battery problem we are really disappointed and crossing fingers that it gets fixed in preparation for our drive to Ibiza!

 

[Nikki]

Hi all. Tracy Hope it gets fixed for your trip. We’re having the same issue. 2nd Battery won’t charge via hook up or long drives. Waiting for an appointment. Tried all the fixes (thanks to all on forum) with no luck. Feel like we’re in most threads now with issues on child lock, battery and sink tap motor keeps whirring (elastic band is current fix ), roof wouldn’t lower (fingers crossed that is now sorted). Love the van but starting to get fed up with the the hassle of it

 

[Mony]

Hi all. Tracy Hope it gets fixed for your trip. We’re having the same issue. 2nd Battery won’t charge via hook up or long drives. Waiting for an appointment. Tried all the fixes (thanks to all on forum) with no luck. Feel like we’re in most threads now with issues on child lock, battery and sink tap motor keeps whirring (elastic band is current fix ), roof wouldn’t lower (fingers crossed that is now sorted). Love the van but starting to get fed up with the the hassle of it

I've had this issue a few times, originally requiring the software fix, and subsequently resets by VW technicians. The last time I was advised that you should always switch off the remote end of the hookup cable before disconnecting from the van, otherwise this confuses the charge controller and causes the charging issues and cable warnings. I've not had a repeat of the issues since following this advice. Hopefully VW will provide a permanent fix to this crazy issue at some point

 

[Nikki]

Mony - thanks top advice. This is something we already do but good to know we’re doing it correctly

 

[Paul White]

1) Cable charge error
2) Sink tap not returning to stop position (I to used an elastic band).
I had both of these issues, tap was replaced , noticeable how quiet the motor is now. Please note access meant that the dealership had to disconnect the gas pipe under the sink and perform a Gas pressure test in order to maintain warranty.
I downloaded and printed the above fix for the cable issue and gave it to the dealership, they told me the mechanic used it and was grateful.
I did ask for a root cause for the cable issue but they were unable to give one.
FYI the tap issues have been seen before at this dealership. It’s interesting that not all Owners are members of this forum, just think how many defects are being seen by VW across the UK and the EU. Hopefully these are finding their way to the designers in Hanover, Germany.
The dealership was Sinclair Van Centre, South Wales.
What do you mean by turning off the remote end of the hook up cable?

 

[nickyboy83]

Mony - thanks top advice. This is something we already do but good to know we’re doing it correctly

I have the tap issue too ;-) Think our vans must be related! We share the tap, childlock & battery issues albeit the last one is fixed now.

 

[Nikki]

vans deffo related! This forum keeps me sane. Fingers crossed our second battery gets fixed.

 

[Nikki]

1) Cable charge error
2) Sink tap not returning to stop position (I to used an elastic band).
I had both of these issues, tap was replaced , noticeable how quiet the motor is now. Please note access meant that the dealership had to disconnect the gas pipe under the sink and perform a Gas pressure test in order to maintain warranty.
I downloaded and printed the above fix for the cable issue and gave it to the dealership, they told me the mechanic used it and was grateful.
I did ask for a root cause for the cable issue but they were unable to give one.
FYI the tap issues have been seen before at this dealership. It’s interesting that not all Owners are members of this forum, just think how many defects are being seen by VW across the UK and the EU. Hopefully these are finding their way to the designers in Hanover, Germany.
The dealership was Sinclair Van Centre, South Wales.
What do you mean by turning off the remote end of the hook up cable?

Thank you on tap advice
Second Battery - that is the issue for us as it won’t charge via hook up or long drive. Tried all the fixes on forum.
Cable - we remove the cable from hook up before removing from van.
I think VW Germany are on their summer holidays

 

[Paul White]

The digital manual states to turn off the circuit breaker affix cable switch on circuit breaker. Obviously this is a safety recommendation but it may help in avoiding this cable issue.
VW it seems do not have registered techs to perform the Gas habitation test. I’ve learnt today that Hereford and Swansea out source to approved suppliers.
I’ve booked mine in for a test next week at a cost of £114 which Swansea have an agreed to refund me.