Cant find fuse from battery to PDU

[Paul Ashdown]

Like another writer I have no 12V when not plugged into mains. New battery, new charger upgraded as previous blew up.
Think fuse from battery may be problem but cant find . Some say it may be under the battery box which is screwed down. The wires from battery do go under the box which is odd as it is in opposite direction to PDU. If I remove battery box will i find it? If not where is it?

 

[Dustydog]

Welcome Paul.
It will help if you tell us make model and year please. The main fuse can be in a number of places but mine is close to the battery Inside the B Box.

 

[Jcloughie]

Hi Paul, and welcome.

Follow the live feed from the battery, if you have a mover there would be two. Ignore the heavier one that goes to the mover. The other wire should have an in-line fuse in the first couple of feet.

I think that is true for most vans. Perhaps not yours.

John

 

[Paul Ashdown]

Thanks for your replies and I should of mentioned that my van is a 2007 Lunar Lexon EW Twin Axle. I do have a mover which was fitted a couple of years ago and I can see the fuse for this which is screwed down inside a small black box , so no problem there and the mover is wired straight into battery so still operates, I have a feeling that i will find the fuse under the battery box but it does seems strange that any right minded company would do this but perhaps Lunar are the exception. I am pretty sure its not in battery box as I have a good idea of where everything is except this fuse. Frankly I never use the van on a site without 230v and so I guess it will work OK but not sure if running like this is detrimental to other parts of the system. Bearing in mind last year when I was away the charger blew up and everything failed . Bought new battery and fitted an external charger under seat into the battery box and charged it up that way.

 

[Jcloughie]

Trace the wire I referred to before to the first connection you find. Which might be the distribution fuse box. And test for voltage. If you don’t have a multi meter, one of these would do:

Draper Screwdriver & Circuit Tester | Toolstation

Tests for electrical potential at any low voltage point in the system. Supplied with 750mm of insulated cable with crocodile clip.

www.toolstation.com

If dead, you then know the fault lies prior to this which narrows down your search.

John

 

[Paul Ashdown]

Good thinking and I do have a multi meter and it confirmed I do have voltage running from battery as there is a connector just in the van under seat and by the battery box . Disconnected and put multi meter on and got 12.6 volts however after the connector the wires go under the box and I have tugged to see if just pushed under but to no avail. Tomorrow i am going to remove or at least lift the battery box and of course I will first remove the battery - which is a monster and I can hardly lift.

 

[Dustydog]

Have you looked in your handbook? The Lunar online ones say the inline battery fuse is just outside of the battery compartment, no more than 500 mm from the battery. I use a secure step and wooden blocks to slide the battery out of the compartment. Then lift away

 

[Paul Ashdown]

Great minds think alike . I use an old caravan step which is just the right height so I also slide tray and battery out but getting back is a little harder. I have looked in handbook and cannot find any reference to position of fuse. I am looking forward to looking under the battery box today to see if its there.

 

[otherclive]

Have you looked in your handbook? The Lunar online ones say the inline battery fuse is just outside of the battery compartment, no more than 500 mm from the battery. I use a secure step and wooden blocks to slide the battery out of the compartment. Then lift away

Likewise and after having a battery handle break on me I always then carried it by the tray.

 

[Beachball]

Hi Paul welcome to the forum my fuse is very close to the battery in our caravan

 

[Paul Ashdown]

I have just removed the battery box and all the sealant which will have to be done again. However the fuse is not under the box but the red and black wires go under box into a loom which goes back in direction of PDU. Still no fuse to be seen and I have taken off PDU and looked behind where all wiring comes in and no fuse. But what does it look like and how big is it and what colour. As already mentioned there is a rats nest of wires and could be hidden ?
My manual mentions an in line fuse holder but does not show or say where it is. Perhaps I should ring Lunar ( Joke )

 

[Dustydog]

There are various types of in line fuses,within their own holder.I assume you have traced the red cable all the way back to the rats nest? Have you tested the circuit continuity . Our Woosie King a few years ago found his battery fuse next to the motor mover control box. He’s moved it back to near the battery.

 

[Jcloughie]

I have just removed the battery box and all the sealant which will have to be done again. However the fuse is not under the box but the red and black wires go under box into a loom which goes back in direction of PDU. Still no fuse to be seen and I have taken off PDU and looked behind where all wiring comes in and no fuse. But what does it look like and how big is it and what colour. As already mentioned there is a rats nest of wires and could be hidden ?
My manual mentions an in line fuse holder but does not show or say where it is. Perhaps I should ring Lunar ( Joke )

When you find it it will be obvious.

O

Similar to the picture.

Continuity is everything. The break in power has to be somewhere. Perhaps a disconnection at the 12 volt distribution board.

Using your multi meter. You can pierce the insulation at intervals. Keep going until you find it’s dead. Bear in mind, you may have continuity and the problem might be in the earth.

John

 

[Paul Ashdown]

Thanks for the info and I have a fuse exactly as shown on my battery charger which I purchased
to keep in car. So if that's the type in caravan I would spot it but not seen yet. So far I've got a loose battery box . a loose pdu and a rats nest to show for my efforts. I'm off to cut down a tree it's easier.

 

[otherclive]

They are infuriating aren’t they. There’s no guarantee one was ever fitted, such is quality control in caravans. Rats nests seem to be endemic as well.

 

[Ferrodo]

Just to add to the saga. My main fuse (20 amp) is located inside the caravan, under the right hand seat and directly behind the battery box. Now it’s not in the red battery lead but connected via two green and brown ( if I recall correctly) wires. These wires disappear under the battery box and I assume will somehow connect to the main battery leads. I know that this is the main fuse because if I pull it then the van looses all power. Subject van is a 2016 Swift Conqueror.

 

[Paul Ashdown]

Thanks again for the help but I am getting fed up with trying to find the fault and would really like to hand it to an expert. I have a good electrician PB electronics but he is too far away and works from home so no place to leave van I would ideally like someone who specialises in caravans near to Ramsey in Cambridgeshire. I have used Pioneer Caravans in Eye but not sure how they are on electrics. They did fit my mover a couple of years ago and hope they did not cause any of my current problems.

 

[Buckman]

Thanks again for the help but I am getting fed up with trying to find the fault and would really like to hand it to an expert. I have a good electrician PB electronics but he is too far away and works from home so no place to leave van I would ideally like someone who specialises in caravans near to Ramsey in Cambridgeshire. I have used Pioneer Caravans in Eye but not sure how they are on electrics. They did fit my mover a couple of years ago and hope they did not cause any of my current problems.

Check on here for an Approved Workshop Scheme technician in your area.

 

[Jcloughie]

Or any auto electrician should be able to sus it out. As I suggested earlier. First thing is to keep checking on from the battery on live and negative to find at what point it becomes dead. The problem is then known to be prior to the last test.

John

 

[Paul Ashdown]

Thanks John but now booked in to Pioneer Caravans and surprised that they can look at it next week .Another company is booked until end of June. Lets hope they can sort it .

 

[Dustydog]

Thanks for the update Paul.
let’s hope these guys sort it out and make sure the main battery fuse is placed near the battery for the future. Please let us all know the final outcome

 

[Jcloughie]

Please come back with a conclusion Paul.

John

 

[Paul Ashdown]

Hi John and all,
Took my van in yesterday to Pioneer Caravans in Eye , Peterborough and they said I could collect next Monday. However got a call this morning and it's already done and bill is £64 which is a great outcome. I spent more yesterday in the showroom where I purchased a double collapsible armchair for £80 .It is so comfortable and easy to erect.
Not sure yet as to what caused problem but did ask them to fit an easily accessible fuse should i ever need to change it. By the way I did fit a new battery restraint instead of the original which was so awkward to tighten and when I did pull it it ripped off the retaining
bracket. So the new one is made from a leather belt which i cut to size and drilled at both ends . This was then screwed into the original holes in housing and tightened. I did it again just below so have got two restraints. OK so you do need a screwdriver to undo but not a great problem. I will let you know what caused my original problem and more importantly where the fuse was.

 

[Jcloughie]

Let us know if they tell you what they needed to do, I am intrigued.

John

 

[Paul Ashdown]

Not technical but this is what I purchased