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Battery light on.

Discussion in 'Motors' started by Kennysevenfold, 27 Dec 2017.

  1. Kennysevenfold

    Sgarrista

    Joined: 9 Sep 2008

    Posts: 7,945

    Location: Glasgow

    Morning.

    Late last night i came out, started the car to defrost it/heat it as i have a baby on board was around -2, i left my headlights on, radio on and heated front and rear heated windscreen, fans etc and jumped back into the house for 10mins

    When i came back out the window heaters had went off and the battery light had came on.

    I had an issue 4 months ago with the battery light coming on and had a brand new alternator fitted and it had been fine since.

    Would this be a battery issue? The car started fine though.

    55 plate mondeo tdci 2.0.

    Cheers
     
  2. pigeonguyuk

    Wise Guy

    Joined: 11 Dec 2012

    Posts: 1,472

    Location: Bangor - Northern Ireland

    The car is 11/12 years old and if still running on the original battery it would be a good place to start. Might now b struggling to hold its charge when the colder weather hits.
     
  3. Kennysevenfold

    Sgarrista

    Joined: 9 Sep 2008

    Posts: 7,945

    Location: Glasgow

    Cheers! Just got me thinking as the car started fine, mibi too much drain on a failing battery while on tick over?
     
  4. HoneyBadger

    Mobster

    Joined: 2 Aug 2016

    Posts: 3,537

    Location: Kent

    Do you know how old the battery is? It'll either be that or the Alternator not supplying enough current to it.
     
  5. Kennysevenfold

    Sgarrista

    Joined: 9 Sep 2008

    Posts: 7,945

    Location: Glasgow

    No not got a clue, was in the car when i got it about 2 years ago, and didnt look remotely new back then.
     
  6. no idea what

    Capodecina

    Joined: 5 Oct 2009

    Posts: 10,775

    Location: Lincolnshire

    All that electrical load on at once will be a huge current draw. If you do an alternator test on a healthy alternator and battery at idle, it will likely fail the test as they can't keep up with the current draw at idle, with the front heated screen on as that's the biggest power draw.

    If you do have a poor battery then it most definitely wont help at all.
     
  7. ShiWarrior

    Capodecina

    Joined: 20 Oct 2002

    Posts: 21,851

    Location: Oxon

    I would change the battery for sure

    Euro Car parts do a good voucher offers , so get a descent Bosch, lithium-ion one with 5 year guarantee
     
  8. Finglonga

    Wise Guy

    Joined: 20 Aug 2008

    Posts: 1,818

    Location: Stafford

    The alternator needs to be spinning at a certain RPM to start charging when you start the car. With all that current draw and if the engine hiccups the charging may cut off and not start again intill the initial RPM is met by the alternator again. His the light remained on or did it go out when you revved the engine?
     
  9. Diagro

    Sgarrista

    Joined: 3 Jun 2012

    Posts: 9,504

    The thing that got me here was that you left the car ALONE to warm up whilst turned on!

    Do you actually want to have it stolen?
     
  10. andicole0

    Soldato

    Joined: 12 Sep 2005

    Posts: 6,319

    Location: Robertsbridge

    Also ilegal if it was on the road.
    Andi.
     
  11. Iamzod

    Mobster

    Joined: 7 Dec 2002

    Posts: 3,578

    Location: UK

    Mk3 Mondeo TDCi's have some sort of electric aux heater built in that comes on below certain temperatures which i believe is a bit like a glow plug. That along with all the above will have been drawing some epic current.

    If it's the original Motorcraft battery it'll have a first charged date stamped on it.
     
  12. Finglonga

    Wise Guy

    Joined: 20 Aug 2008

    Posts: 1,818

    Location: Stafford

    Wasn't going to mention it as seems common practice for most nowadays even though makers say start the car and drive away. Insurance do not pay out if the car is taken either when left like that.
     
  13. grudas

    Capodecina

    Joined: 12 Mar 2008

    Posts: 21,065

    Location: West sussex

    Depending on location, I'd never leave my car alone in London where I lived.. but where I live now there's not a soul awake or anywhere near my car..
     
  14. Le Clandestin Brun

    Sgarrista

    Joined: 6 Sep 2007

    Posts: 8,623

    As long as you lock the car it's a minor.
     
  15. Uncle_Gravy

    Mobster

    Joined: 11 Aug 2012

    Posts: 4,339

    Location: S.E Wales

    Always let my car warm up while I go eat my breakfast, It's on my driveway, it's not going anywhere....TBF I do live in a more remote side of my town where the street consists more of the older generation.
     
  16. sovietspybob

    Mobster

    Joined: 25 May 2008

    Posts: 2,941

    Location: North Wales

    It really depends where you live, i do it any day its been frosty as i have a big driveway where you can't really see the cars from the road and we also live in the middle of nowhere.

    If i was living in the center of Manchester i doubt i'd do it :p
     
  17. bainbridge

    Mobster

    Joined: 9 Dec 2009

    Posts: 4,018

    Location: Bristol

    Why leave the headlights and radio on if the car is being left to warm up unattended?
     
  18. NickK

    Capodecina

    Joined: 13 Jan 2003

    Posts: 19,068

    A little fact on the focus TDCI that may apply to the Mondeo too - there are two alternators you can get (the cheap one and the more expensive part) for the titanium trim with all the gadgets etc I needed the higher power one but the first replacement they used the cheap one. I found that out when I fitted the second one myself and the cat seemed far more with it (faster charging etc).

    The battery and alternator seem to kill each other off if one dies, so you may as well replace the battery if the alternator is putting out enough power (iirc it was 15V or so across the battery terminals). Measuring current is far more difficult (needing a clamp meter).

    Hmm not sure about an aux heater - perhaps in cold climates (Norway for example) but the ford front window that has a heating matrix in it sucks power - same as the heated seats and the air heater matrix.

    In Norway they have a remote for starting and warming up the car from the house :)