Battery gauge shows zip, but car starts and runs

Discussion in 'General Motoring' started by Katrina, Mar 7, 2009.

  1. Katrina

    Katrina Guest

    What the heck? My '89 740 Turbo sat for awhile due to a flat tire. It
    started up on the first try last week. Today we've got some nice warm
    weather so I put air in the tires and took it around the neighborhood.
    I noticed my battery gauge, the needle is all the way to the left,
    besides the number "11" when it used to be right smack dab in the
    middle between the 11 and whatever is on the right side. A 16, I
    think.
    Anyway...I drove it right back to the house, parked it and now I
    patiently await your thoughts and advice. Thanks in advance!
     
    Katrina, Mar 7, 2009
    #1
    1. Advertisements

  2. Katrina

    James Sweet Guest


    Try tapping the gauge with your knuckle while the car is on, sometimes
    they stick when the lubrication dries up.
     
    James Sweet, Mar 7, 2009
    #2
    1. Advertisements

  3. Katrina

    Andy Guest

    Yeah, my fuel gauge ('88 760GLE) does this and will drop to completely
    empty from time to time. Luckily I know that I can get 500km to a tank
    :)

    Cheers,
    Andy.
     
    Andy, Mar 8, 2009
    #3
  4. That's your voltmeter. It shows either the resting battery voltage (with the
    engine off, but the key on), or the charging voltage (with the engine running).
    A normal, fully-charged battery should show between 12 and 13 volts on the
    gauge when just sitting, and around 14.5 volts when the engine is running and
    the alternator is doing its thing. Is your gauge always sitting at 11, or does it
    start at zero, then pop up to 11 when you turn the key on?

    Do you, or anyone you know, happen to have a pocket-sized voltmeter you could
    connect to the battery terminals to verify what the battery and alternator are doing?
    If not, a lot of places can check the charging system for you with a few simple tests.
    Some might even do it for free. Try the local gas station (if they have mechanics and
    service bays), or Autozone, or some other auto-parts stores.
     
    MasterBlaster, Mar 8, 2009
    #4
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.