12 volt fuse box (1 Viewer)

[Stewart marr]

Hi
I have a 2006 ace Milano, I recently replaced the leisure battery and now I can no longer power the control unit from the leisure battery it works from engine battery and when plugged in to mains. I have read about the 12 volt distribution fuse box but can’t find it in my van. Can anyone please help me?

Thanks in advance
Stewart

 

[Spriddler]

I recently replaced the leisure battery and now I can no longer power the control unit from the leisure battery

Has it worked at all on the new battery?

 

[Stewart marr]

spriddler

No, when I changed the battery it blew a fuse which I have changed and checked but thought there might be a fuse box so wanted to check that. It can’t be the control panel as that works from the engine battery and mains? I am scratching my head and running out of ideas.

Stewart

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[Stewart marr]

spriddler

No, when I changed the battery it blew a fuse which I have changed and checked but thought there might be a fuse box so wanted to check that. It can’t be the control panel as that works from the engine battery and mains? I am scratching my head and running out of ideas.

Stewart

 

[Spriddler]

When I changed the battery it blew a fuse......

Perhaps there was (still is) an existing fault between the (old) battery and control panel which killed the old leisure battery and is now still causing a problem?
I don't have a wiring dia but I would start by following the battery to control panel cable using a meter to trace how far there is voltage between the new battery and the control panel. Not easy I know to follow a cable's twists and turns and disappearance behind panels etc. but unless you can find another (possibly blown) fuse that's about all you can do.

 

[movan]

THIS COULD BE A VERY STUPID ANSWER AND I APOLOGISE IN ADVANCE

..When I bought a new leisure battery .. the same happened to me. It transpired that the guy who fitted it had put the connectors on the wrong way round as the diagram he was following .. stuck on cover .. was upside down.. (that was his excuse anyway.

When the contacts were put on differently it worked again.

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[Stewart marr]

The polarity of the battery terminals is correct that was what blew fuse first time around so I know that bit is good will have to try chasing the cable back to the control panel but it goes off behind fitted cupboards and I can't see any fuses other than the 2 straight off the battery and a bigger 30 amp fuse to control panel which are all good.
Thanks
Stewart

 

[Spriddler]

The polarity of the battery terminals is correct that was what blew fuse first time around.........

Some electronic control 'black boxes' can be ruined by being fed incorrect polarity................

 

[Stewart marr]

Where would the black box be. I am having trouble understanding why it works with engine battery and mains but not leasure battery thanks for your help so far
Stewart

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[TheBig1]

check there isn't another fuse by the battery on the negative feed, as this would also blow if you reversed the polarity

 

[138go]

If you have connected the battery up the wrong way you may have damaged the electronics in the control box. Fuses don’t blow instantly something may have got through. A lot depends on the design of the panel electronics and wether they thought it necessary to put in a circuit to stop accidental wrong way round connection. You may find that the fuse that’s blown is on the control panel.

 

[autorouter]

Looks like no Ace Milano owners have seen this thread yet, so this may be better than nothing. The distribution box has at least half a dozen 12V fuses, probably a dozen. Some of these boxes have the mains control inside too - you can tell by seeing if there are circuit breakers like those in a house mains consumer unit - but often they are in a separate mains distribution box.

The location will be somewhere out of the way but not too difficult to access. Inside the wardrobe at the back, or in one of the storage areas under the seat, are good places to try first. Otherwise, try one of the top cupboards or an outside locker. It will probably be quite near the leisure battery. Or near mains inlet socket.

If you find it/them, let us know the make and model, it's likely to be in many other motorhomes.

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[Spriddler]

I am having trouble understanding why it works with engine battery and mains but not leasure battery

The engine and the leisure battery probably each have their own dedicated fuse.
The fact that it works on Mains is a bit of a red herring as the 240v Mains and the 12v systems are by necessity totally separate systems from each other (except for the leisure battery charger which is powered from the Mains).
Your 5 free posts are now used up so to continue posting you'll need to invest £15 in joining up - and it's worth every penny.

 

[gus-lopez]

 

[Spriddler]

There's a 2006 Ace Milano 2.0 JTD manual and wiring dia's in the link below but I haven't time now to check it out for you but it shows that there are separate fuses for each of the two batteries.

https://www.manualslib.com/products/Ace-Milano-2-0-Jtd-2006-3659898.html

and another one for a 2009 model here:

<Broken link removed>

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[autorouter]

Looking at the diagram in @Spriddler's link, I'd say there's only one fuse between the leisure battery and the control panel, which is the 20 amp one right by the battery. If that's OK then if the control panel doesn't work it probably got damaged when the battery was connected with reverse polarity.

If you can gain access to the panel, the wire from the leisure battery is coloured brown with a thin blue tracer stripe. First check that you get 12 volts on this wire as it comes into the panel. If not, there's a bad connection or break in the wire. If there's 12 volts, there may be a fuse where it connects to the board. Look around that area for signs of burning/fused circuit board tracks.

The manual says it's a Sargent AC85 unit, maybe others can advise about repair/replacement.

Also check that the leisure battery charges when the engine is running. You can check this by using a multimeter on the battery terminals. Read the voltage when the engine is stopped. That should be between 11 and 13 volts. Then start the engine and read the voltage again. The voltage should rise by at least a volt, depending on how charged the leisure battery is. If it gets to over 13.6 volts it's definitely charging.

If it doesn't charge, there seems to be a fuse box with 4 fuses, which will probably be near the split charge relays, possibly under the bonnet. Fuse number 3 (20 amp)