leisure battery - connected but not working

[bobby_badger]

Hi

Total newbie here. Just bought a Bongo (97 TD 2.5 automatic) and the seller said it has a leisure battery which they never used so they couldn't guarantee/comment on its use. We bought it on that understanding, but as it has a second battery under the bonnet and it is wired up in some way we'd obviously like to get it working if possible. Nothing inside works unless the engine is running or the key is in the ignition. There's a hob/sink unit at the back which has a couple of 3 pin plugs on the side which are wired up to some sort of a box inside the unit and a power invertor, but I'll worry about that later.

I have been reading on this forum and looked at the FAQs (NB the link to the beginner's guide is broken - https://igmaynard.co.uk/bongo/memberson ... ricity.pdf) so I know more than I did but that only makes me realise how little I know . I know about a split charge relay but I can't see a box under the bonnet that could be that. I know that some Bongos had a second starter battery but from what I can make out there would be a switch on the dashboard for using that, but there is none.

If any knowledgeable people on here would be kind enough to look and suggest how the battery is connected I will at least have a starting point/know what needs fixing.

Under the bonnet I can see the second battery is wired up and earthed;

From what I can see the wiring is fused and runs along a pipe to the fuse box;

Then as far as I can see it then goes through the bulkhead into the vehicle;

Could it be the two batteries are running in parallel?

Sorry for the lengthy post - thanks for looking. Any tips gratefully received!

thanks,
Iain

[Bob]

Hi Iain

That certainly looks like a leisure battery set up, not the second starter fitted with the 'cold start' pack. For interest the switch operates a valve in the exhaust system, it doesn't control the battery.

If the last owner never used it the battery may be beyond recovery. You can do a basic check with a multi-meter, or any accessory shop will have a test meter so I'd check that first.

Since the converters all have their own methods it's difficult to say what's wired where, but Geoff may have some thoughts, with luck.

[bobby_badger]

Hi Bob. The seller did say the battery was working as it had been used in their caravan but I'm not sure when. I guess checking to see whether the battery is flat is a sensible starting point. Thanks.

[g8dhe]

Yup can't see any sign of a Split Charge Relay, but some of the smaller types used for caravans (not really suitable for campervans) are easily hidden away. You would need to follow the +ve terminal wiring on the LB back to see just what is connected to it. One thing I do note is that looks very much like mains grade wiring being used, which really isn't a good idea, its way to soft to allow flexibility in house wiring, whilst for vans the vibration and abrasion the insulation really needs automotive grade which is a much tougher physically, type of insulation.

[bobby_badger]

Thanks Geoff. I have just carefully tracked back from the LB and I can't see it goes through anything. In fact I said in my original post that it went into the fusebox but I don't think it does. It seems to go from right to left and meets up with the cables from the starter battery (pictured below) and then goes through the bulkhead;

Assuming that is what happens can you suggest what that is supposed to achieve? Would the two batteries be running in parallel?

Thanks for your comment about the grade of wiring. I suspect I will be having this rewired by someone qualified so they will no doubt use the correct grade. But first things first I will test the LB to see if it is dead or alive.

[g8dhe]

Some installations put the SCR in the cabin itself, not under the bonnet which is not a good move as it increases the wiring length a LOT! You will probably have to track it thru the bulkhead and find out where the feed goes.

[bobby_badger]

Yikes - will do. Thanks.

[Bob]

The glove box is fairly easy to remove, gives you a lot more space to look and work.

[bobby_badger]

But where am I going to keep my gloves!

[bobby_badger]

Hi again

Update on my leisure battery situation. A friend at work who has some experience in these matters had a look under the bonnet with his meter and discovered a couple of things.

Firstly, the leisure battery only measures about 6v so clearly is not charged/healthy. He thought it was worth trying to charge it so I took it out tonight and according to the indicator on the top of the battery it needs charging rather than water adding;

So I connected it to our Halfords battery charger and it said it was charging it for 10 or 15 seconds and then the light indicated that it was charged ("Ready and Maintaining"). As it's an old style battery which can be topped up with distilled water and I had most of a bottle of Halfords "Battery Top-Up Water" to hand I opened up the 6 'vents' on the top and topped up 4 before running out of water on the last 2. I connected it to the charger and it seemed to charge for a little longer before the charged light came on. I'll get some more top-up water and try again but it's probably a goner isn't it?

Also, the leisure battery seems to go through this box;

It's some sort of a relay - could this be a split charge relay? It seems to be a Hella 12v 4RA 003 437-04. I can't find much about it online and what I can find doesn't mean much to me (eg https://www.wantitall.co.za/industrial/ ... b07dh2rq4g). Or maybe it is totally unrelated

I realise I'll have to get a new leisure battery and have better wiring done sooner rather than later but if I can last a couple of months as it is that would be better cash-wise.

[Bob]

With the voltage that low it's worth trying to charge it, but I fancy you'll be very fortunate to recover it.

[Bob]

But where am I going to keep my gloves!

Make a careful note of how you remove it, then you could pop it back.

Or you could keep them in your pocket.

[bobby_badger]

Joking aside Bob, the wiring goes through the bulkhead by the steering wheel side rather than the glove box/passenger side

[Bob]

Ah...

My idea won't help then.

[g8dhe]

I think I would be changing that battery, if its been left without water /electrolyte in for a period the lead surface will be damaged and it might take a charge but the capacity will be way down as only half the plate area will be working properly.

Yes that relay is almost certainly the one doing the Split Charge function, its plenty adequate for the role as its rated to 60 Amps. It will probably be either Ignition switched or being fed from the Alternator check lamp (not a good choice of circuit).