Section : Electrical Equipment

Alternators, dynamos, lights, wipers, etc.

Dead battery

Posted By : Mark Heaps, 10-Mar-2004, 07:58pm

Could someone help me.
My Mark IV spit is losing charge if I don&195;&8218;&226;&8364;&8482;t drive it. It takes only about 12 hours to drain and then I have get a jump. After the jump it drives fine for as long as I want thus eliminating out alternator problems (I think) at my local tssc meet a earth strap problem was discussed, how do I test for such a problem or could I be something else any advice would be gratefully appreciated.
Cheers Mark

Followups :

Dead battery

Posted By : James Carruthers, 10-Mar-2004, 08:14pm

Could be your alternator - if the diodes are dead...

When mine did that I could see the volts falling on the multimeter... try chraging up the battery and disconnecting the alternator and see if it still drains...

James
- Dead battery
  
  Posted By : Charles Lowe, 10-Mar-2004, 11:16pm
  
  Mine had the same problem of the battery dying overnight, found out the battery was still under guarrantee so took it to halfords who said it was fine. Ended up using a kill switch for a couple of months, to stop it flattening. I had to take apart the dash to fit a new ammeter and found that the rear windscreen switch was held on with a bit of bluetack and was shorting the whole time. Fixed it up properly, and i now have no problem with losing charge.
  - Dead battery
    
    Posted By : David Styles, 11-Mar-2004, 10:12am
    
    my last dead battery problem was on a car where the guy had wired the overdrive to a permanent live.
    
    If you parked it and left the overdrive switched in...
    (and with it in 3rd or 4th gear!)
    
    you got a dead battery in the morning....
    took me a couple of goes to work out what it was.
    
    they are so annoying battery drains aren't they ?
    
    I'm lucky that I have the little cups on the ends of my leads that go onto my battery on my latest car.
    I don't bother with the screws to hold them down, as the interference fit seems fine... So its a moments work to twist them off.
    
    Otherwise I'd fit a kill switch.
    
    good luck chasing it round and finding the problem... if its not a duff battery, then it looks like a multimeter job.
    - Dead battery
      
      Posted By : Mark Heaps, 14-Mar-2004, 06:52pm
      
      Thanks for all your help but i think i have the problem solved, a simple trip to halfords, an interesting look from the sales assistant as i dont think he had ever tested a battery on a car without a bumper kit and neon lights, he found the battery to be duff and for a mear &163;24.99 offerd a replacment job done, tested it this morning and it started first time so hopefully problem solved. He also gave me some advice. The battery is under warrenty for three years, after two and a half leave your lights on drain the battery, take the battery in, they will test it find it dud and give you a new one, a bit cheaky but if they put an offer on why not take advantage of it
      Cheers again mark
Dead battery

Posted By : Brian Archibald, 10-Mar-2004, 09:53pm

Are you sure that your battery is ok, as it could be a duff cell.

Charge it up and disconnect the earth side. Leave it overnight and reconnect in the morning. If it starts ok then it eliminates the battery.

If you want to check the alternator output make sure the battery is charged, start the engine and turn on all the electrics you can (lights, heater etc). Put a multimeter across the battery terminals and it should be reading 14v+ at 2500rpm.

The next step is to check the circuits fed from the fuses (perhaps someone can tell us what each one supplies) and disconnect one at a time, overnight, to try to find the circuit that is draining the battery.

Hope this helps and good luck

Brian
'79 1500
- Dead battery
  
  Posted By : Mark Stradling, 11-Mar-2004, 11:58am
  
  Yea, I'd get the battery checked out.
  
  My stereo keeps a live connection to the battery, to keep the clock running, and the stereo's alarm active when the ignition is off. Now we aren't talking much drain here, but it was enough to wipe out the battery in 7 days.
  
  New battery and... well the charget hasn't been out of the box for months!
  - Dead battery
    
    Posted By : Mark Heaps, 12-Mar-2004, 04:28pm
    
    I have a live feed to the stereo also, didn't realise that it could be pulling enough power to drain the battery, might try dissconecting that first,. i hope it is somthing simple, i have an auful feeling i will be chasing this one for months will keep you all posted thanks for you help
Dead battery

Posted By : Philip Rosenberg, 10-Mar-2004, 10:31pm

My 1500 was doing the same thing. Almost every morning, especially if it was frosty, there just wasn't enough charge in it, but I could drive up the M1 for 2 hours with no problems. I put of buying a new battery for a few weeks as I was skint then last week I realized it was still under guarentee. Drove to Halfords, they stuck a multimeter on it and I explained the problem. They said "yeah it's duff" and replaced it for free. Now all cured starts every time again.