Sudden loss of 12v power

Discussion in 'Tech/Mech General' started by Camperian, Jan 8, 2008.

  1. Camperian

    Camperian

    Joined:
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    Been on HU for the last 2 months, so decided to run the main engine to give the vehicle battery a charge.:Smile:

    Wouldn't start on ignition, but started comfortably on aux battery.

    Everything was fine for ten mins or so and I decided to drop the jacks. The dash which had been showing an initial charge of 13+ amps suddenly jumped to zero.

    No vehicle system now at all, no headlights, indicators, side lights, dash lights including warning lights. Everything else is fine.:cry:

    Removed battery and put meter across (thanx KANDS for showing me how to use it) and it shows anything from 8v upwards each time I tested it:RollEyes:

    Now put it on booster charge overnight.

    Fleetwood Southwind 1995
    Chevy 7.4L petrol

    Any ideas?

    Ian
     
  2. American Dream

    American Dream

    Joined:
    Aug 20, 2007
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    Location:
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    Have you blown a fuse?

    Any corrosion on the main vehicle battery terminals?

    You've been on EHU for 2 months.Has the vehicle battery been charged during this time.8V across terminals suggest a dead battery.

    Check usual things.Battery terminals clean and tight.Battery to chassis earthing good and connections clean.Fuses.
     
    Last edited: Jan 8, 2008
  3. pappajohn

    pappajohn Funster Life Member

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    anything less than around 9.5volts and you have a plastic box with some lead in it to stop it blowing away.:ROFLMAO:
    even if you get a 12v/13v reading straight after charging it the chances are it will discharge as soon as you turn on the ignition.:Sad:
    new battery needed i think.

    john.

    ps...... dont forget your leisure battery is designed for slow discharge not the 500/600ah needed to crank a cold engine so you will damage your leisure battery.
     
    Last edited: Jan 8, 2008
  4. scotjimland

    scotjimland Funster Life Member

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    I agree with Pappajohn , below 10v the battery will probably never recover. .

    Fit a new battery then check the voltage with the engine running, should be around 14.4v , if not check for a blown fuse.
     

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