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Dead Battery on cold mornings

I have a 2002 Ford Focus and every time we have cold weather my car battery will be dead in the mornings. After I jump the car I can drive it and it will be fine the rest of the day but the next morning the battery is dead again. I seem to have this problem every winter and I end up buying a new battery every time only to have it die the next year.



I've wondered about the starter motor but never had it checked. I also wondered if there was a drain on my battery but I've checked it with a voltage meter on several occasions and there doesn't seem to be one.



Any suggestions?

Comments

  • edited February 2010
    How old is that battery? If original, it's time to replace it. You can have the charging system and battery checked for free at many auto part stores. They generally do a good job.

    A Volt meter will not going to tell you much about drain with the engine off. You need a sensitive amp meter.
  • edited February 2010
    Find a shop that specializes in automotive electrical/electronic systems and have them test the car's charging and electrical system. You shouldn't need a new battery every year.

    How far do you drive each day? If your daily mileage is very limited perhaps the alternator is not able to charge the battery enough to keep it fully charged.
  • edited February 2010
    Do you do a lot of short trips? If so, the battery may not be getting charged enough. I use a Battery Tender to top off the batteries in my vehicles if the voltage is a little low (12.6 V - fully charged, 11.9 V - fully discharged).

    www.batterytender.com

    The Battery Tender is pricey, but still much cheaper than replacing a battery every year. A trickle charger could be used also. For example, Harbor Freight has this one for $9.99 regular price and is often on sale for 1/2 price.

    http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42292

    My 2000 Blazer has driveability problems if the battery voltage is 12.2 volts or less (~50% charge).

    Has the alternator output been checked? A weak alternator will kill a battery and vice versa.

    Ed B
  • edited February 2010
    The battery I just replaced was still under warranty so I'm guessing it was less than 2 years old.
  • edited February 2010
    The starter isn't connected to the battery until the starter solenoid is activated so that isn't the trouble. You need to check the current drain on the battery using your meter instead of checking the voltage. To measure current you need to set the meter fuction to measure current and place the meter leads in series with the negative battery cable and negative battery post. Keep the connections isolated from each other and anything else on the car. Normal current draw should be less than 35 milliamps when systems have gone into the sleep mode. By pulling fuses one at a time you should be able to see what path the current is on when the current drops down after the correct fuse is pulled.
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