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Another flat battery

Discussion in 'General Banter' started by Paul Rice, Feb 12, 2020.

  1. Paul Rice

    Paul Rice Zorg Guru (IV)
    Supporter British Zeds The M44 Massive

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    Thankfully not mine but a new Z4 owner with a flat battery?
    Had new battery fitted (correct one for car) terminals nice and tight
    14v going through battery when charged and engine running
    All courtesy lights extinguish as required including glove box and boot

    Code reader suggests a fault with radio but non specific?
    Car locks itself when left with keys out of ignition and left for a short while?
    Battery totally flat after 7 days

    Thoughts lead to Alarm but any suggestions would be most welcome.
     
  2. Rha

    Rha Zorg Guru (V)
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    I would start with isolating any radio extras that’s been added Paul then remove radio power fuse. Both these options will still only give you an area (depending what scanner is available)after you cancel faults then run car again. Alarm same thing although isolating the alarm may not be an option as they’ve usually got a back up batt somewhere. Vehicle electrician would be the way I would go if it’s nothing obvious, even at their high daily rate it may be worth it, quicker than going round in circles for hrs. BMW main agent will cost £100+ Just to put their code reader on it so usually out the question. Sounds like the previous owner may have had the same problems hence UNW. Key fob plus spare is a bit of a long shot cos it's locking itself, so I would remove key from area or wrapp it in kitchen foul, at least you'll know it's not that if it still locks itself. Look in all vehicle history for any elect work that's been carried out recently. Hope this helps, it's just hard to fathom when the electrics play up as it's really a specialist field. Good luck.

    Roy.
     
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  3. Nodzed

    Nodzed Zorg Expert (I)
    Supporter British Zeds #ZedShed M Power

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    One common offender is a broken tab that switches off the light for the center console/box that's behind the driver/passenger where the satnav / CD player is. look and see if that light is staying lit even with the cover closed.
     
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  4. Geoff Crispin

    Geoff Crispin Zorg Guru (III)
    British Zeds

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    I am no expert but would suggest put a code reader on it, maybe a short somewhere.
     
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  5. Paul Rice

    Paul Rice Zorg Guru (IV)
    Supporter British Zeds The M44 Massive

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    Code reader suggest problem with radio but non specific
     
  6. mid life crisis

    mid life crisis Zorg Guru (I)
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    If you disconnect the battery -ve cable and then put an ammeter between the battery terminal & the cable it should tell you if a current is being drawn, you could pull the fuses out one by one to find out it should indicate what is still live.
    Gary
     
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