Main battery going flat!

[4inabongo]

Hello! Having solved a problem for me brilliantly in January I turn to the wise people of the Bongo forum once again for help. I'll just give you the background and see if you can come up with any thoughts. Have a 1999 AFT 8 seater and we had a removable back conversion fitted last July which also had a leisure battery fitted at same time with a split charge relay so that the leisure powered the 12v sockets, blinds and radio. A compromise I realise, but we couldn't afford full hook up.Last autumn when van stationary on drive for more than a few days main battery going flat as pancake. AA men came and went scratching heads but got it going again. This went on for months. In end got a new main battery last month out of desperation but low and behold flat again last week! Grrrr! AA man came out and suggested to us a really good old fashioned auto electrician nearby in Bridgend to have a look at it as he said he was getting some odd readings he didn't understand! So take it there and they say there's a 0.11 leak on main (split charge seems ok tho) and in the end the best thing he could think of to do was to put an isolator in which stops all the appliances drawing power off as it cuts into main harness(???) but I think that now isolates the leisure battery so I presume that we keep it on when driving to charge leisure on split charger but turn it off when van stationary (although this doesn't make much sense when we're camping cos we need leisure battery - I suppose we can switch off when asleep!) It will solve the 'parked on drive for week' problem I suppose but I would have thought isolating the main battery would have made more sense! I can already feel the sighs from those of you who know your Bongo electrics. Show me mercy! Can you come up with a better suggestion of a permanent fix?????

[Northern Bongolow]

the isolator he fitted should be from the starter battery, this will allow you to use your pre charged leisure while camping, but will preserve the starter batt.

what split charge system have you fitted, is it willinton or another type. inferior ones tend to weld the terminals together and allow draining back from the starter batt via the leisure, or bad charging of the starter batt. i used to use a 30 amp voltage sensing relay to switch charge from the starter when charged to the leisure batt, but these lasted only approx 1 year, ive now started to use a 70 amp set up.

seems strange though how the good sparky could measure the drain but couldnt isolate it.
by the size of the drain it does sound like you have an ALDI or LIDL radio fitted----still on the starter batt. these are known to still draw a sizeable lump, even when off.
maybe fit a radio isolator switch in both feeds, see if that helps.

[New Forest Terrier]

The radio is probably the most likely culprit. I had an Aldi radio which managed to flatten both leisure and starter battery plus other electrical funnies. The cure was either an isolator switch on the radio or change to a Japanese type radio. I replaced the Aldi radio with a Sonny and all problems were cured.

[4inabongo]

Yet again you are marvellous people who come up with answers!!! I feel slightly in awe that Supreme Beings have replied so quickly! Thank you! I suspect you are right and we have an inferior spilt charge relay. Where do I get hold of the better one you suggested? It's not an ALDI or LIDL radio but an ALPINE from Halfords. It is connected to leisure, not main battery so may not be culprit although if leisure is drawing charge off main then radio not helping. He was a proper sparky. Loads of people have recommended him since. It was in for 2 days but I suspect, and I am finally learning, that we need to go to someone who knows Bongos inside out and back to front! Target Mini in Waunarlwydd are great - it's just an hours drive from me! They do all our servicing etc; So, if you let me know where I can get that spilt charge relay that does a better job will get one of those but may use isolater sparky's fitted when Bongo less used in winter just to be on safe side!

[g8dhe]

The car radio's have TWO power feeds. One is a permanent supply to retain the memories etc. and in the Bongo is fed from the top left 10 Amp fuse (along with several other circuits). The other power feed is via the Ignition switch and the fuse is the top right 15 amp fuse, this normally supplies the full power requirements. However not all radio's are designed equally and some draw much more power than is good for the battery from the permanent supply - this might well be your problem!

[Northern Bongolow]

i just fitted one of these. looks the biz, and fitted in mins.
just move what you want on to the leisure bat via an independent fuse box with the correct size fuses fitted.

http://www.ebay.co.uk/itm/SPLIT-CHARGE- ... 4d0ecb6310

[jaylee]

I seem to remember problems like this solved in the past by finding a fitted power inverter by a previous owner as the culprit too..?!!

Try looking behind the rear panel trim in the boot where the cigarette lighter socket is & see if you can see a box of tricks..?