Leisure battery not charging while driving

[BobbyOrbit]

Hi. We had some problems with our very old leisure battery (holding charge, sulphur smells etc), so replaced it with a new one. However, it seems not be charging when we drive and hence it's drained when we arrive at a campsite. Once we have external power it seems to charge up no bother, then loses that charge again after driving for a while.

We probably need to get an expert to look at it, but does this suggest a problem somehere between the engine battery (also new) and leisure battery? I assume wires connect these to enable charging? Apologies for my probable ignorance and many thanks in advance. Cheers!

Robert

[Mocki]

I think you need someone to help you , unless you have a multimeter and know how to use it , in which case we can guide you through it 

without knowing what set up you have its going to be hard to say much more at this stage 

normally you would have a alternator triggered relay joining the main van battery and the leisure battery together when the engine is running and the alternator charging and disconnecting when the engine is switched off so the batteries operate independently 

first thing you need to do is establish if the alternator is working correctly , out putting 14v and if that is reaching the starter battery .