New Van - Split charge relay wiring issue?!?!

[al*mk1]

Hi All,

A newbie to the T25 world but not 80's VW's - "My other car is a Mk1 Golf Gti".

I hope someone can help me with a split charge issue?
The below pic shows some partially connected wires for what I believe is a split charge relay that I found under the seat of my T25.

The red and black cables at the bottom of the pic run into the dash loom/ignition and are both fused.
These connect to the yellow and blue wires respectively on the relay.
The relay then has the grey and green wires which are not connected to anything. Should these be simply connected to the terminals of the leisure battery or should it be one to positive terminal and one to chassis/earth?

If they have ever been connected, they have been pulled and forgotten about at some point.
The leisure battery doesn't appear to be receiving any charge during mains hookup in or during driving.

I would test the output across these two though my multi-meter looks to be dead as everything I touch is -1v!

My leisure battery is currently around 9.1 volts which my "intelligent" charger is telling me, though it will not kick into charge mode, as if it doesn't recognise the battery.


Screenshot from 2017-06-02 13-38-24 by www.pix-al.co.uk, on Flickr


The van is an AutoSleeper conversion if it helps, though the scotch locks make me think this is someone else's addition?
Any pointers would be greatly appreciated!

Thanks,
AL

[CovKid]

The relay should have numbers associated with the terminals - more use than coloured wires which aren't much indication of anything. Mind you, that said, OKO relays seem to be unique to themselves (just Googled a few). I'm assuming it doesn't have regular spade terminals.

Charge the leisure on a regular charger for an hour so it at least gets to a voltage the intelligent one can then recognise. It may be knackered though if its been at 9v for some time....

In your position, I'd just pick up another relay (40amp minimum) and wire it up as per WIKI. They're cheap enough (fiver) and better than trying to guess with a non-standard relay.

[al*mk1]

Cheers CovKid.

You are right - the OKO doesn't have spades. It has solder points with the wires fixed in place. I couldn't see numbers like a conventional relay either.

The diagram you posted does look like most of those I found so I may be best starting again.

AL.

[spherehopper]

I have used a company called Vehicle Wiring Products many times in the past. They even sell a pre-wired relay to save making up yourself.

http://www.vehicle-wiring-products.eu/p ... arge-relay" onclick="window.open(this.href);return false;

[Oldiebut goodie]

OKO are usually seen on printed circuit boards. May be one of them.

[al*mk1]

I have used a company called Vehicle Wiring Products many times in the past. They even sell a pre-wired relay to save making up yourself.

http://www.vehicle-wiring-products.eu/p ... arge-relay" onclick="window.open(this.href);return false;

Thanks.

That looks very similar to the OKO unit (That was inside a plastic case). That one has more wires though.

[CovKid]

For simplicity sake (and it worked fine for me for ten years), follow the diagram above and just pick up a 40amp relay. It will do the job fine and as everything will be marked/numbered, its easy to follow. I don't use one now as my solar is doing it all, but nowt wrong with a basic relay and I doubt theres much need for you to buy a 'kit'.

[al*mk1]

I have now managed to charge the battery. I borrowed a charger that did recognise though went from "Charging" to "Full/Maintenance" in about 5 mins!?. I disconnected and put my charger back on which did now recognise the battery at around 12.1v.
It took around 30h at 3.8Amps (Max advertised charging current) before it decided the battery was full, so I am hopeful that the battery has some life left.

I am happy to plug the charger in the day before a planned outing to ensure I am topped up and I am also looking at a solar solution that I can use when on-site, or possibly even leave connected permanently if I am happy I can mount sensibly on the fibreglass roof.

What sort of wattage is your solar kit, CovKid?
My battery will only run a few lights in the evening and the Fridge ignition system and maybe some USB plugs for mobiles. I am thinking a 50W panel should be fine to keep things topped up?

50W/12v = 4.1A

75Ah battery at 4.1A per hour = 18 hours of solid sunshine to charge a fully flat battery.

I appreciate the panel is not likely to give the full 50W (or anywhere near) all of the time, but is my logic/maths right?

[Oldiebut goodie]

At 9v starting voltage that battery is sha**ed! Very unlikely that it can be recovered.

Maths/logic not right. A battery should only be discharged to 50% of the rating so you should only be recharging 37.5Ah not 75Ah, ie you only have 37.5Ah usable capacity in a small battery like that.

[al*mk1]

At 9v starting voltage that battery is sha**ed! Very unlikely that it can be recovered.

Maths/logic not right. A battery should only be discharged to 50% of the rating so you should only be recharging 37.5Ah not 75Ah, ie you only have 37.5Ah usable capacity in a small battery like that.

Ah. Ok. The maths is right, but the values are not.
I get that a battery should only get to 50% so charging the full 75Ah is not realistic. Charging 37.5Ah is better and would only take 9 hours of full output power.

I didn't think the battery could recover but upon full charge being indicated, I disconnected the charger and tried the electrics. Lights all worked very brightly and new 12v tap/pump was gushing compared to the poor trickle I had just before everything died completely. Only time will tell if the battery lasts or if indeed it is knackered.