Leisure Battery Charging

[rolling_stone]

Hi. I've had a leisure battery fitted to my T6 conversion last June, which has been working fine till this week.

Came to turn a light on today, after two hours of driving, and there was no power in the battery whatsoever. Nothing will turn on.

Has anyone any ideas of simple things I can check? I'm no electrician. Could it be something that has just tripped?

Thanks.

 

[Pete C]

How do you know there was no power in the battery - could it be charged, but a fuse has blown ?
How is the leisure battery charged i.e. what device is between it and the alternator/vehicle battery.

The more info you can give us the more help we can give.

Pete

 

[rolling_stone]

I only assume it has no power because nothing turns on. Even the control panel's LEDs are all off. I've found the auxiliary fuses under the driver seat, but should the fuses I'm looking for (that might have blown) be somewhere else?

In terms of how it's charged, I can only assume it's DC-DC as it's a T6 and it's been working fine till today.

Thanks.

 

[Pete C]

Presumably the company that installed the battery gave you instructions, and told you where the fuses are ?

From what you have said so far, I would start with the DC-DC charger. Can you get a photo of that ?

Pete

 

[sparkzer]

the first thing i would do is get my multimeter out...do you by chance have one?

do you know where the leisure battery is located?

 

[rolling_stone]

Presumably the company that installed the battery gave you instructions, and told you where the fuses are ?

From what you have said so far, I would start with the DC-DC charger. Can you get a photo of that ?

Pete

Thanks. I think I found the fuses: This one under the bonnet? And then this one near the leisure battery.


Is it likely one of these two have blown?

Is this the DC-DC charger?


I don't have a multimeter... but I've just ordered one!

Thanks in advance.

Paul

 

[Pete C]

That’s not the DC-DC charger. It is likely to be under the seat alongside your leisure battery.
There are probably other fuses under there too.

Check that fuse under the bonnet to see if it has blown.

Pete

 

[rolling_stone]

Okay. Will do. Thanks.

 

[Dilbert]

Don't jump in feet first! As with all electrical fault finding you need to divide the problem in half. The first thing I would do is measure the voltage on the battery. This then tells you if you have a charging fault or a secondary supply fault.

Around 12V on the battery means it's charging OK and you are looking for faults/fuses on the secondary supply.

If the battery is flat, then you have a charging circuit fault. Check the voltage with engine running too.

 

[Dellmassive]

As above,
There should be a main fuse on a thick cable by the starter battery.

This should run to the Aux battery under the seat, there should be a second large fuse at that location too.

In between there should be a Dc-dc charger or a VSR or a relay.....

It may be that you have one of the large fuses blown or the fused 12v feed that triggers the VSR or dc-dc may be blown.

You need to start with a multimeter and get some readings....

 

[rolling_stone]

Okay. Thanks. The multimeter is arriving today (god bless, Amazon prime ) so I'll try that first and report back. So if I take a reading from the leisure battery when the engine's off and when it's running.

Having never used a multimeter, I'm assuming it's as simple as just placing the two contact points on the + and - on the battery??

Thanks.

 

[Pete C]

Yes, but make sure the meter is set to measure DC voltage, NOT current.

Pete

 

[Pete C]

While you are waiting for Amazon, you could open that fuse holder under the bonnet, and see if the fuse has blown.

Pete

 

[rolling_stone]

While you are waiting for Amazon, you could open that fuse holder under the bonnet, and see if the fuse has blown.

Pete

Thanks, Pete.

just done that and it's not what I was expecting actually (see photo) So is the fuse just the thin strip of metal? If it is, then it looks like it hasn't blown. I also tried changing the red '10 amp' fuse near the battery but neither has brought the power back on.

 

[Pete C]

Correct. That fuse is fine.

Can you get any photos of what is beside your leisure battery? Perhaps slide the seat forward or backward fully.

Pete

 

[Dilbert]

We don't know the battery isn't charging yet.....

 

[rolling_stone]

Hi again. So, assuming I'm using the correct settings, these are the multimeter readings with the engine off, and then the engine running.



Which should read around 12.6, right?

Also, here's a snap of what is next to the leisure battery - I can see another fuse like the one under the bonnet but haven't checked that one yet - it's a bit fiddly to get to, and wasn't sure if it was safe to go poking round under there?!


Thanks in advance. All help much appreciated so far!

Paul

 

[Severals]

I had a similar thing happen to me, after finding a flat leisure battery, went on a previously planned 40 mile round trip the Ablemail didn't charge.
I took it back to the converter and we almost returned the Ablemail DC-DC charger as it was showing about 1V output to the battery, after contacting Travelvolts we were told that the charger won't work at less than a 10.5V charge in the battery.
Plugged it into the EHU to bring it above the 10.5V and the Ablemail started to charge.
I don't know if other chargers have this cut off rating.

 

[Dilbert]

Your battery is definitely flat! Your meter is correctly set. And it does not appear to be charging.

Worth checking the other fuse but first check the voltage on the first fuse you uncovered (one probe on the fuse, the other on the leisure battery negative terminal) to see if there is around 12V here or not.

If no volts, check the fuse under the bonnet.

This assuming the first fuse you found is on the supply side of the CTEK charger.

 

[rolling_stone]

I had a similar thing happen to me, after finding a flat leisure battery, went on a previously planned 40 mile round trip the Ablemail didn't charge.
I took it back to the converter and we almost returned the Ablemail DC-DC charger as it was showing about 1V output to the battery, after contacting Travelvolts we were told that the charger won't work at less than a 10.5V charge in the battery.
Plugged it into the EHU to bring it above the 10.5V and the Ablemail started to charge.
I don't know if other chargers have this cut off rating.

Thanks for this. So EHU? Is that just plugging it directly into the mains to charge?

So just to clarify, for my non-electrical mind, you're saying because the leisure battery dropped to a voltage below 10.5v, it no longer was able to be charged by the engine?

How could it drop that low? And then that's a fault with the DC-DC charger then is it? Because it must be quite common that people need to charge their leisure batteries from below 10.5v when they're 'off grid', no?

Thanks.