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Anon
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12volt short

If I disconnect the neg termanel,set avo to 20 volt connect avo neg to the earth strap and touch the neg terminal with avo pos probe.I get a 12volt short.I have checked all of my wiring and cannot find a short.So I think it must be in the van wiring.Has anyone any ideas of where to look.All help greatly reseved.THanks,Jim.

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Wed 28 Jan 2015 @ 20:54 Edit this messageQuote this messagePMQuote this message
Colin Birch
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What you are seeing is not a short, it's just the reading across the battery. If anything at all is turned on (including interior lights etc with door open) it will give a circuit to the pos terminal of the battery. Your meter will then see this circuit and give you a 12V(ish - depends on your battery) reading. So, unless you are 100% certain that nothing is 'on' then you will get a 12V reading with what you are doing. Let's see how my artwork looks :-

Battery Earth Battery
term bulb Strap Term
+O---------XXX-------o O-
12V

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Colin Birch - CF-UK Admin
Pontypridd, S.Wales
The Bedford CF Web Site
http://www.cf-uk.co.uk

Wed 28 Jan 2015 @ 22:33 View Colin Birch   Email Colin Birch   Colin Birch Home Page   Edit this messageQuote this messagePMQuote this message
Anon
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When you reconnect the battery do you get a strong spark that you can see and hear. If so remove all the fuses and then disconnect and reconnect battery to see if sparking has stopped. If it has put fuses back one at a time looking to see if one sparks. That then identifies the circuit with the power drain. As Colin said about interior lights etc don't forget if you have a radio with a permanent live for the memory presets or a digital clock they could be picked up from any wire that was handy depending on who installed it.
Andy

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Thu 29 Jan 2015 @ 15:41 Edit this messageQuote this messagePMQuote this message
Anon
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short cercit

Thanky you for you response.My van does not have a fuse box on the engine or lights.Yes there is a large spark on reconnecting the neg or on disconnecting same.I have taken out all of the fuses on the lesure battery .This is how I cam to the conclusion that it is on the van side.I have no digital clock and disconested the interior light.Cheers Jim.

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Thu 29 Jan 2015 @ 20:54 Edit this messageQuote this messagePMQuote this message
Colin Birch
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Hi Jim

Just because you've taken the fuses out doesn't mean everything is disconnected. You don't know what mods have been made by previous owners. If it was a short circuit you would have a very high current draw and, if not fused, lots of melted wireing or a mass of smouldering camper! Does your battery run down quickly when not used? Does your meter have a current range (at least 10A) and do you know how to connect your meter as a current meter?

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Colin Birch - CF-UK Admin
Pontypridd, S.Wales
The Bedford CF Web Site
http://www.cf-uk.co.uk

Thu 29 Jan 2015 @ 21:55 View Colin Birch   Email Colin Birch   Colin Birch Home Page   Edit this messageQuote this messagePMQuote this message
Anon
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Hi. I see on an earlier post you had a problem with your alternator wiring. remove and insulate the wires from the alternator and see if this stops the the sparking. The diagram for early in line fuse cfs shows 3 wires to the alternator.

Andy

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Fri 30 Jan 2015 @ 13:52 Edit this messageQuote this messagePMQuote this message
Anon
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short

When I replaced the alternator I pealed the outer from the wiring and found that 3 of the wires went to noware these I took out,leaving a thick brown and a thin black with a yellow line this is for the warning light.As I said The fuses I mounted are all ok.My van does not have a standard Fuse box fitted by Bedford as the lights have a heat sensor on the switch.The short has killed a battery i.e it is now a perminant short between the terminals.The short is pulling 6 amps at 12 volts.I don't know why wires are not burning,infact I wish thay would then I could find the short.Cheers Jim.

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Fri 30 Jan 2015 @ 21:24 Edit this messageQuote this messagePMQuote this message
Colin Birch
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Hi Jim
If it was a short it would draw a much higher current than 6A. You say you have a leisure battery so I'm assuming you have a two battery setup? Which battery is the problem with, van (engine) battery or camper (leisure) battery? What type of charging arrangement do you have, Zig or split charge relay?

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Colin Birch - CF-UK Admin
Pontypridd, S.Wales
The Bedford CF Web Site
http://www.cf-uk.co.uk

Sat 31 Jan 2015 @ 17:03 View Colin Birch   Email Colin Birch   Colin Birch Home Page   Edit this messageQuote this messagePMQuote this message
Anon
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short

Hi Colin,I have taken the leisure battery out.The prob is on the engine side.I have the split charge relay.Cheers Jim.

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Sat 31 Jan 2015 @ 21:07 Edit this messageQuote this messagePMQuote this message
Colin Birch
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I would start by disconnecting the feed to the split charge relay from the engine battery. Check the leads that go to the leisure battery and make sure they are dead. How many wires are there connected to the positive battery terminal? Unfortunately the CF1 was wired different to the facelift/CF2 as it doesn't have a fusebox which makes finding faults a real pain (especially over the net!).

Just a thought, do you have a 2 or 3 way fridge? It's not switched to 12v is it?

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Colin Birch - CF-UK Admin
Pontypridd, S.Wales
The Bedford CF Web Site
http://www.cf-uk.co.uk

Sat 31 Jan 2015 @ 21:35 View Colin Birch   Email Colin Birch   Colin Birch Home Page   Edit this messageQuote this messagePMQuote this message
Anon
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like colin says check the fridge 6amps at 12volts = 72 watts which is about the wattage for the fridge element

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Sat 31 Jan 2015 @ 22:46 Edit this messageQuote this messagePMQuote this message
Anon
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short

Hi lads,I have now disconnected The entire leisure side and still have the short.I will start checking each wire again.The switch mech on the egnition seems well worn so I am looking for said switch.Would a TK switch be the same? My fridge is a 2 way i:e 12 volt and gas and is not switched on.If I had hair I would be pulling it out,so there is something to be said for being bald lol.Cheers Jim.

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Sun 01 Feb 2015 @ 15:01 Edit this messageQuote this messagePMQuote this message
Anon
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I have checked all of the wiring and cannot find a short,as the egnition switch seems worn I am trying to replace it.Has anyone any idea what switch will fit? All sergestions considerd.That is if possible.lol.Cheers+beers,Jim.

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Sat 07 Feb 2015 @ 21:08 Edit this messageQuote this messagePMQuote this message
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