fuse keeps blowing???

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steve480

fuse keeps blowing???

Post by steve480 » Sun Mar 14, 2010 7:08 pm

hi folks
i have an in line fuse that keeps blowing on the wire that goes from the positive connection on my starting battery that runs into the split charger unit. this wire has an in line 15amp fuse that blows every time i start engine. just fitted new leisure battery but i had fault before fitting new leisure battery. my starting battery is less than a year old. it was working fine till the van was off road for a few months while getting new head fitted. none of the wiring was touched that i know of, the charge light on my power management system is on ok, fridge running fine, but the small pump for water supply isn't working (would this have anything to do with fuse blowing???) does anyone have any other ideas in what could be causing fuse to keep blowing ??????????????? :? #-o .
cheers.......steve
francophile1947
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Re: fuse keeps blowing???

Post by francophile1947 » Sun Mar 14, 2010 7:14 pm

Sounds like the leisure battery is flat and drawing enough current to blow the fuse (15A is very low :? )
Try charging the leisure battery up with a charger and try again.
John
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hembramacho
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Re: fuse keeps blowing???

Post by hembramacho » Sun Mar 14, 2010 7:16 pm

What kind of split charge unit is it? I'm sure the in-line fuse on my Willinton unit is a 50 amp one - don't know if that's got anything to do with it if yours if only a 15amp?

Andrew
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steve480

Re: fuse keeps blowing???

Post by steve480 » Mon Mar 15, 2010 1:51 pm

hi
not sure what type of split charger it is but its not very good, wires are very thin. just tried 30 amp fuse same result just blows. leisure battery brand new & fully charged. dissconnected pump incase it was that :x :x . would like to get willinton set up, but cant afford £105 at the moment. is there anything else that could be causing fuse to blow ??????? steve
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g8dhe
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Re: fuse keeps blowing???

Post by g8dhe » Mon Mar 15, 2010 3:37 pm

Its also a trifle worrying that you appear to have only a single fuse !
Leisure batteries with a charging relay should have three (3) fuses associated with them;
  1. Fuse from the Starter battery to the relay, close to S/B, charging circuit
  2. Fuse from the Leisure battery to the relay, close to L/B, charging circuit
  3. Fuse from leisure battery to the circuits being powered, close to L/B, load circuit
If you have replaced one of the charging circuit fuses with a larger one then the other one should be blowing!
The description that the Fridge is running OK whilst that Water pump isn't sort of implies that the L/B is OK - assuming it is being fed from the L/B, however the fault as described implies that the L/B is flat so its strange that anything is running!!
Can you confirm just what the L/B feeds, and do any of those devices work OK, also how many fuses are there associated with the L/B ?
Geoff
2001 Aero V6, AFT, full side conversion.
steve480

Re: fuse keeps blowing???

Post by steve480 » Mon Mar 15, 2010 6:08 pm

hi geoff,
the leisure battery is brand new & fully charged (fridge running fine which is powered by L/B) i have 1 fuse at L/B & the 1 fuse at the starting battery (this is the 1 that keeps blowing). so i only have the 2 fuses which were 15 amps, tried a 30amp with same result blowing. i've never had what powers what explained to me but i think the only 2 things powered by L/B are the fridge & water pump ( i think :? ). i dissconnected pump to rule that out, fuse still blowing, everything else is working ok. when i first got van 18 months ago it all worked fine & i havent touched anything. my old L/B was an 85ah but my new one is 86ah, dont think that should make any difference.................steve
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g8dhe
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Re: fuse keeps blowing???

Post by g8dhe » Mon Mar 15, 2010 6:41 pm

I would suggest two things to start with;

1. The fuse close to the L/B, follow the lead and see where it goes to if its running through the bulkhead it will almost certainly be the Load fuse, best to follow it inside and see if it goes direct to the Fridge and water pump or if it goes to the Fuse box down by the drivers knee, if the latter then it may well have been wired to takeover the internal lights / blinds / radio etc.

2. There must be a lead from the relay to the L/B, unless the relay is mounted on the L/B terminal itself (quite possible , in that case there should be a fuse close to the relay instead), then that lead should have a fuse in it, as otherwise if that lead gets damaged and touches earth then the L/B will discharge through the lead and could possibly cause a fire :-(


Do you have a multi-meter which you can use to check the voltage on both batteries ? If you do then, starting with the Ignition OFF, check both voltages at the batteries themselves, both should be around 11.5-12.5 volts. Now start the engine but DON't rev it up, and check the voltages again, the S/B should be showing above 13.5 volts within a few seconds normally, the L/B if it is being charged will be at the same voltage - but if the fuse blows then the chances are the either that there is a fault between the Relay and the L/B or the L/B isn't as charged as you think it is. If you haven't charged the new L/B on a separate charger before putting it in the vehicle, then now is the time to do so! What sort of Fridge is it (Compressor or cool box style) ?
Geoff
2001 Aero V6, AFT, full side conversion.
steve480

Re: fuse keeps blowing???

Post by steve480 » Mon Mar 15, 2010 7:27 pm

hi geoff
i did charge the L/B before fitting, my fridge is a compressor type. to be honest with you have havent got a clue i think i need the help of an auto elec. threr are 2 wires running off the positive lead off L/B so thats why i assumed it powers the fridge & pump, i will try to follow wires to see where they go & get back to you.thanks for your help....... steve =D>
steve480

Re: fuse keeps blowing???

Post by steve480 » Thu Mar 18, 2010 3:45 pm

hi all,
thats me got the problem of blowing fuses all fixed. took it to an auto electrition. as soon as he looked at it right away he said wiring was very poor & too weak for the job it was doing. so he ripped out the whole lot & rewired using much heavier wiring & 40 amp fuses. all working & charging the way it should be now. i bought the van from car dealer in kilmarnock but it was converted by a company in yorkshire. the quality of convertion isn't all that good when you consider what they charge for it. at least thats it all working now ready for the open road. thanks to all that tried to help me its much appreciated.
steve :D
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Re: fuse keeps blowing???

Post by MountainGoat » Thu Mar 18, 2010 4:54 pm

Pleased to see that you are now sorted Steve, hope that it did not hit your pocket too hard. I had the same sort of problem when I had my bongo converted by a Nottingham converter. Dandywarhol took one look at the set up and said that it looked as if they had installed a sandwich box and filled it with fuses. Dandy advised that I scrap the lot and install a Willinton Kit which I did. I have had no problems since.

Tony
Former SGL5 Owner Jeep Cherokee 2.5CRD Burstner Ixeo Time it585
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