Leisure battery issues - update & advice please...

[Sportstest]

Hi all,

I posted some weeks back that my leisure battery was not holding charge. Finally booked into my local VW van centre, one of the leisure batteries was dead/faulty and was replaced under warranty (the one in the rear under wardrobe), the second (under the passenger seat) was ok, and so not replaced.

Van returned, but then got Air Bag failure warning, also I wasn't convinced that issue was solved, so took to the dealer I purchased the van from.

Upshot, I was given the "all clear" no problems with van at all.

I cycled the 50 miles to collect the van yesterday afternoon, and after the van had been sat for 4/5 days battery showing as having a charge of only 20%.

Suggested the issue might be the console above rear view mirror, rather than the battery, so this was swapped out from another van, and I was sent home. Drive home took approx. 2 hours, and by the end of the drive battery was showing 100% charge.

This morning, I was not surprised to see the charge showing as down to 50% again. BUT the display console does not show a consistent reading....jumping from anything from 20% to 80%, and briefly up to 100% before falling and settling again to around 50%.

Has anyone else experience this? Any idea of problem or solution?

My worry is I have a 7 day trip planned next week, where after the first few days, I am likely to be in the same place for 4 days, but without EHU. I don't want to continually be running the van engine to keep power to heaters and fridge.

HELP PLEASE!!!!

Here is a quick video of part of the issue I am facing....

Thank you

Garry

 

[Max-Felix]

Sometimes it is best to forget the dealer and call up a local mobile experienced auto-electrician. Within a very short time he should be able to test for drains and properly check the battery condition. Yes, you will have to pay but it will save a lot of back and forth hassle with a dealer who is probably not an expert in these things.

 

[T6 CFO]

I'm presuming engine off. Ignition off and nothing at all plugged into 12 volt supply?


Mike

 

[MattBW]

Pop the van on EHU for 24 hours if possible to give the battery the best possible chance. Then see how it goes, it really makes a big difference.

 

[Sportstest]

I'm presuming engine off. Ignition off and nothing at all plugged into 12 volt supply?


Mike

Yes Mike, nothing plugged in. Ignition off. Prior to going back to the dealership the van had been on EHU for 4 days continuously (with the fused switched to correct position).

 

[Sportstest]

Pop the van on EHU for 24 hours if possible to give the battery the best possible chance. Then see how it goes, it really makes a big difference.

Thanks, had tried that before it went into the dealer. Hasn't done the trick unfortunately.

 

[WelshGas]

Thanks, had tried that before it went into the dealer. Hasn't done the trick unfortunately.

If 1 battery was dead/faulty this will have affected the 2nd Leisure Battery. Both should have been replaced.

The other ??? possibility is the 80 amp fuse that connects both. That could have failed and you are in fact only using 1 battery.

 

[AlanC]

I agree with WG. If one battery is dead, then the other will be weak as it is the same age.
I am not certain if there is a diode in the circuit to stop the seat battery trying to charge the dead wardrobe battery. Someone may have a circuit diagram to check this out.

Better to have changed both batteries at the same time, easy to say after the event.
Can you get another fitted before your trip?

Alan

 

[Sportstest]

Thanks both. I think they have ordered me a second leisure battery, so hopefully they can make the swap either tomorrow or Friday to give me the weekend to check everything is working properly.

The additional info on the 80 amp fuse is really helpful too.

Thank you

 

[Sportstest]

Electrical diagram

 

[AlanC]

Thanks Sportstest.

From that diagram there is not a diode fitted to the either of the two leisure batteries. They are connected directly in parallel as it says. The engine battery is isolated from the leisure batteries by the split charge relay.

That means if one leisure battery dies, the other will try to recharge it and thereby damaging itself in the process.

When you run the engine, the engine battery will get a full charge first, and when fully charged, the split charge relay will kick in and supply a charge to the other two batteries. If one is dead the charge will go to this one as well and a smaller current to the healthier battery, but not enough to fully re-charge it.

So the answer is to change both leisure batteries together.

Alan

 

[Sportstest]

Thanks Sportstest.

So the answer is to change both leisure batteries together.

Alan

Just had an email from the dealer (yes at 7:10 pm) two new leisure batteries on order, and accompanying fuses.

Thank you for the input everyone

 

[rod_vw]

Thanks Sportstest.

From that diagram there is not a diode fitted to the either of the two leisure batteries. They are connected directly in parallel as it says. The engine battery is isolated from the leisure batteries by the split charge relay.

That means if one leisure battery dies, the other will try to recharge it and thereby damaging itself in the process.

When you run the engine, the engine battery will get a full charge first, and when fully charged, the split charge relay will kick in and supply a charge to the other two batteries. If one is dead the charge will go to this one as well and a smaller current to the healthier battery, but not enough to fully re-charge it.

So the answer is to change both leisure batteries together.

Alan

Almost Alan, the battery isolation relay operates as soon as the BCM (Body Control Module) detects that the alternator is charging, it does not monitor the condition of the main (engine) battery.

In respond to the OP, I would be looking for poor connections in the leisure battery circuit, maybe fuse connections or if I am correct about Cali electrics, the shunt that the control panel monitors battery current flow by.

Rod

 

[Bigted]

Almost Alan, the battery isolation relay operates as soon as the BCM (Body Control Module) detects that the alternator is charging, it does not monitor the condition of the main (engine) battery.

In respond to the OP, I would be looking for poor connections in the leisure battery circuit, maybe fuse connections or if I am correct about Cali electrics, the shunt that the control panel monitors battery current flow by.

Rod

Hi rod,

Does the bcm monitor the charge level of the leisure battery? The reason I ask is my van alway pushes 14.8v at the leisure battery when running even if the van has been plugged in for some time (i.e. Leisure battery charged by mains to full). Should the bcm drop the voltage to stop overcharging?

 

[sidepod]

Thanks Sportstest.

From that diagram there is not a diode fitted to the either of the two leisure batteries. They are connected directly in parallel as it says. The engine battery is isolated from the leisure batteries by the split charge relay.

That means if one leisure battery dies, the other will try to recharge it and thereby damaging itself in the process.

When you run the engine, the engine battery will get a full charge first, and when fully charged, the split charge relay will kick in and supply a charge to the other two batteries. If one is dead the charge will go to this one as well and a smaller current to the healthier battery, but not enough to fully re-charge it.

So the answer is to change both leisure batteries together.

Alan

That's not how the split charge relay works.

When the engine is running the SCR is closed connecting ALL batteries to the alternator to be charged.

When you stop the engine the SCR isolates the starter battery from the leisure battery thus ensuring you don't drain your starter battery whilst using the leisure batteries.

 

[Alec Murchie]

Garry, I have a 2015 T5 and 3 days after first 24hr. EHU (last week), panel shows 30%. I'm presuming one or both of the leisure batteries is not holding charge...Can you confirm VW replaced leisure batteries under 3 year Warranty as mine ends next April?

 

[Sportstest]

Garry, I have a 2015 T5 and 3 days after first 24hr. EHU (last week), panel shows 30%. I'm presuming one or both of the leisure batteries is not holding charge...Can you confirm VW replaced leisure batteries under 3 year Warranty as mine ends next April?

Hi Alec,

Yes my local VW van dealer (who were not a cali specialist) replaced the battery until warranty, but I was still not convinced that the issue had been solved. So I booked the van back into the dealer I bought the van from (Leicester). It took a couple of attempts, but they eventually narrowed the issue down to a faulty relay somewhere. (They told me they pretty much needed to strip everything out, including the kitchen), but all done under warranty, and the issue seemed solved! No problems since!

Good luck!

 

[Jolberg]

Hi Alec,

Yes my local VW van dealer (who were not a cali specialist) replaced the battery until warranty, but I was still not convinced that the issue had been solved. So I booked the van back into the dealer I bought the van from (Leicester). It took a couple of attempts, but they eventually narrowed the issue down to a faulty relay somewhere. (They told me they pretty much needed to strip everything out, including the kitchen), but all done under warranty, and the issue seemed solved! No problems since!

Good luck!

Hi.
I realise you've slept at few times since the battery problem you had on your van, but do you recall which relay was causing the problem? I have a problem which sounds very much like the symptoms you were describing and my local van centre are struggling to locate the problem.
Any further info you have would be most appreciated.
Cheers

Jolyon

 

[Sportstest]

Hi Jolyon, apologies no I don't think they told me. I do remember them telling me they needed to remove the whole of the kitchen to solve the issue.

hope you can get your problem resolved

Garry

 

[Jolberg]

Hi Jolyon, apologies no I don't think they told me. I do remember them telling me they needed to remove the whole of the kitchen to solve the issue.

hope you can get your problem resolved

Garry

No worries. Thanks for answering.