12V issues

Discussion in 'Tech/Mech General' started by gordoncbrown, Oct 28, 2011.

  1. gordoncbrown

    gordoncbrown Funster

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    Hi, I think my battery has packed in. Symptoms. 12 v lights etc work when connected to hook up. But not when disconnected. Battery indicator does not register. Test meter shows battery as 10.8v. Will be away tomorrow so if it doesn't charge from alternator I think it can only be the battery. Apparently it was replaced not long brfore I purchased the MH but looks to be a cheap one. Any advice or tips welcome.:Smile:
     
  2. hilldweller

    hilldweller Funster Life Member

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    Then was the real fault the charger and now the new battery is dead ?

    What voltage across the battery when hooked up ?

    If it's that 10.8V mentioned pull the + connector off the battery to see if it is pulling the charger down and if the charger is working properly it should jump to 14V(ish).
     
  3. chatter

    chatter Read Only Funster

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    No doubt some one that knows will be along soon but i think that somewhere in your motorhome there should be a switch which allows the ehu to charge your battery and maybe this has been knocked to the off position
     
  4. RKE

    RKE Read Only Funster

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    Hi, I had a similar problem after I had collected my van from new.....

    In my case the aux battery had been run down by the cleaners who were preparing the van for collection.

    I had a 30 mile journey from dealers to my home during which time a fuse had blown because the battery was too flat to be charged from the alternator!
    Worth checking all fuses in circuit I think......but I'm no expert by any means! :Wink:
     
  5. Wildman

    Wildman Read Only Funster

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    a run down battery can pull a lot of amps to charge, blowing the fuse in the process. If the battery has been at 10.8 for any length of time it is most likely an EX battery. Do check fuses, and charge relay to ensure battery is actually getting a charge. Does it need topping up or is it a sealed battery. Is it an only leisure battery or one of a pair. Is the switch in the correct position to accept a charge from EHU. Do you need help in using a multimeter to check? If so let us know.
     
  6. gordoncbrown

    gordoncbrown Funster

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    Thanks

    Thanks to everyone for assistance. Found a fuse had gone but don't know the route cause of the fuse blowing. I will be carrying a test meter and spare fuses from now on.:thumb:
     
  7. RKE

    RKE Read Only Funster

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    My best guess would be that at 10.8v the batt would be pulling too much current from the alternator charging circuit and so 'blowing' the fuse.

    Charging via the mains onboard charger would avoid this problem if the batt was allowed to become that discharged..........I think!! :Smile:
     
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