Leisure battery low

Happy New Year All,

 I was on EHU a couple of nights over Christmas in my 1999 Duetto, i had the battery charger on, but my leisure battery voltage dropped to 12v. I have since used a newer portable battery charger, which have upped the voltage to 12.7v, does this mean that my built in charger is no longer working properly?

There's a bit of ambiguity in what you wrote, but if you mean that - with the portable charger attached and powered on - the leisure battery voltage does not exceed 12.7V then the battery has probably had it.

If on the other hand you mean that the battery voltage is 12.7V half an hour after the portable charger was used and then disconnected, it would seem to be in OK condition.

The key test would be to note the leisure battery voltage when idle (no load, no charging) and then connect the EHU (with charger turned on). Voltage before and after should reveal clearly whether the built-in charger is charging the battery.

Hi Roopert,

 I only had time to use the newer portable battery charger for a couple of hours, so i don't think that the battery is the problem.

You need solar!!!!

IanH wrote:You need solar!!!!

I have a 25 watt solar panel connected to my starter battery, this is sat on the dashboard and keeps it in good order. When off grid i also use a folding 120 watt solar panel, but this doesn't fit so well inside. My roof usually has a 9' paddleboard on it, when i'm away in the van, so a bit tricky to put solar on the roof.
My question was more to do with the onboard battery charger and if anyone else has had similar issues or even replaced it with something newer?

The key test would be to note the leisure battery voltage when idle (no load, no charging) and then connect the EHU (with charger turned on). Voltage before and after should reveal clearly whether the built-in charger is charging the battery.

Hi Roopert,

 Last time i connected the built in charger, the voltage from the charger started at around 13.8v but rapidly fell back to 12v, so maybe the charger thinks that the battery is full?

The charger/power supply output voltage should never drop below around 13.6-13.8V. If the battery voltage is 12V then it's not working, or is working but not connected to the battery.

Looks like i need to do a bit more testing / investigating. 
Thanks for your help so far.

It looks like i have a faulty relay or blown fuse, would anyone know where to find the correct relay/fuse, is it the one in the black box above the starter battery?