1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Duff Battery????

Discussion in 'Electrics, Vacuum, Ignition and ECU' started by w44nty, Dec 7, 2012.

  1. w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    My battery on my ML has been a bit weak whilst starting over the last week or 2.

    This morning when I went to start,it turned once and then died,when I turn the key nothing happens but the headlights come on,is this the sign that i need a new battery or could it be something else

    Thanks Steve
     
  2. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    It does look as though the battery has passed its sell by date, ideally you would put a voltmeter over the battery when cranking, I presume it just makes a click when you try and start now.

    The first cold spell brings out the poor batteries

    Do you have a volt meter
     
  3. Naraic

    Naraic Moderator

    Messages:
    10,328
    Likes Received:
    942
    Joined:
    Mar 4, 2010
    Your Mercedes:
    2005 CL500.
    Headlights on...must mean something else. Possibly a bad main earth. Usually when a battery dies...things don't just come on by themselves.
     
  4. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor

    They come on when key is turned in the ignition,it do not normally do that
     
  5. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    Yes Malcolm just a click and the headlights come on,the battery has been noticably weak on starting in mornings over the last few weeks,its been ok during the day whilst in use,it just gave up this morning after 1 turn
     
  6. Naraic

    Naraic Moderator

    Messages:
    10,328
    Likes Received:
    942
    Joined:
    Mar 4, 2010
    Your Mercedes:
    2005 CL500.
    That's very strange...so the light switch is off...but the lights come on?
     
  7. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    Not on modern cars where a relay is used to operate the starter, the voltage can be high enough to allow the lamps to light but not enough to close that relay. A check with a voltmeter is the first thing to do.


    But as it is an ML we know that they get bad earth wires on the engine, there are many post here on this.

    One could prove this by using a jumper lead from the engine to a good ground point on the body
     
  8. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    Niaracs post reminded me of the earth wire problems on an ML, do what I said in my above post
     
  9. Naraic

    Naraic Moderator

    Messages:
    10,328
    Likes Received:
    942
    Joined:
    Mar 4, 2010
    Your Mercedes:
    2005 CL500.
    The way I read it...the lights are coming on, but they are not switched on...waiting for confirmation.
     
  10. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    Yes it seems very strange to me,when my son comes home I will try to jump start it ,if it do ,I would hopefully presume the battery has had it.
     
  11. Naraic

    Naraic Moderator

    Messages:
    10,328
    Likes Received:
    942
    Joined:
    Mar 4, 2010
    Your Mercedes:
    2005 CL500.
    No, don't presume that...look for the reason the lights are coming on...as above, we think bad earth.
     
  12. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    Yes that is exactly what is happening,all the lights come on on the dash,glow plug goes out,turn key no engine turning ,just a click and headlights light up without being turned on or in auto mode
     
  13. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    If it starts from a jump over the battery, then battery,,but why not put the jump lead on a clean part of the engine and to a good chassis or body point and try
     
  14. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    Just been out and looked at battery,there have been some water around the earth terminal caused by the wet weather ,would this cause a bad earth connection
     
  15. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor
    When my son comes home malcolm I will try out,do I just put one lead on the engine and the other end on the chassis and just try to start as normal,I take it then if it starts its a bad earth
     
  16. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    I was thinking while eating that the lights could come on as it could be trying to find a ground point,,I am 100% sure it is that wire, its been deteriorating this last new days and no gone completely
     
  17. Rockall

    Rockall Senior Member

    Messages:
    286
    Likes Received:
    0
    Joined:
    Feb 22, 2012
    Location:
    Donegal Ireland
    Your Mercedes:
    Many
    The battery in my ML just died overnight about a month ago - it would power lights, windows etc but not enough to turn the starter. New battery installed, had to reset radio code and that was it. Gearchanges (auto) a lot smoother as it obviously erased the memory in the box and went back to factory settings.
    Regards
    Bill
     
  18. OP
    w44nty

    w44nty Senior Member

    Messages:
    225
    Likes Received:
    0
    Joined:
    Mar 4, 2012
    Location:
    Thorpe St Andrew Norwich Norfolk
    Your Mercedes:
    ML 270CDI 2002,C180 Kompressor

    Update:

    Car started with Jump Start,drive to my local garage they tested battery it was kaput.

    Fitted new Bosch battery everything ok now,so it was the battery after all(fingers and everything else crossed),wallet now £80 lighter.

    Thanks everyone for your imput and help

    Steve
     
  19. television

    television Always remembered RIP

    Messages:
    164,074
    Likes Received:
    309
    Joined:
    Mar 14, 2005
    Location:
    Daventry
    Your Mercedes:
    2002 SL500, 216 CL500, all fully loaded
    So I got it right in my first post :D So pleased you are OK
     
  20. Naraic

    Naraic Moderator

    Messages:
    10,328
    Likes Received:
    942
    Joined:
    Mar 4, 2010
    Your Mercedes:
    2005 CL500.

Share This Page