How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Steve Your Own Question

Steve
Steve, BMW Expert
Category: BMW
Satisfied Customers: 23488
Experience:  BMW Expert
26942375
Type Your BMW Question Here...
Steve is online now

2008 BMW 118 diesel, which I drive mainly around London on

Resolved Question:

2008 BMW 118 diesel, which I drive mainly around London on short journeys, suffers from low battery problems. A heavy duty battery was fitted on the advice of Hexagon, from whom I bought it new, in 2010. Today I've had the battery charged by a local garage, who had it on charge for 7 hours, but was still drawing 4 amps, which they think is higher than they would expect. With everything switched off, it draws about 0.1 amps but it fluctuates. I've had it recharged before, but, especially in the winter, it runs down. Is there anything I can do about this?
Submitted: 3 years ago.
Category: BMW
Expert:  Steve replied 3 years ago.

hello

 

there are a few options

 

1) you should have a full current draw test or power diagnosis test carried out to verify if there is a faulty component that is drawing more power than it should when the car is off and "asleep". 0.1 amps is a little high, so there may be an issue.

 

if the current draw test comes back all okay, then you have two more options

 

2) change driving behavior since repeated short trips places a heavy burden on the battery and charging system

 

3) put the car on trickle charge each night to ensure the battery never gets too low

 

I know these last two options are somewhat unsatisfying, but repeated short trips are a legitimate concern on new BMWs given the heavy amount of electronics they have - if there is no undue current draw and the alternator is working properly, then the driving habits are to blame and these are the only options.

 

 

Sorry if you were hoping for a different answer, please don't shoot the messenger - I can only give the honest answer, which I have. Please remember that a low rating PUNISHES me for my honest and prompt response, and I receive nothing for my time and answer until a positive rating is clicked.

Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.

Customer: replied 3 years ago.

Your reply is helpful, but can you desccribe what a current draw rest is? Also I only have street parking available, so cannot trickel charge overnight. Any other ideas?

Expert:  Steve replied 3 years ago.

a current draw test involves monitoring amperage draw with the car in sleep mode, then pulling fuses on by one to see when the draw stops or drops off. this will thus identify the problem circuit that is draining the battery. Also, if you have anything aftermarket installed, that should be removed

 

if there is no undue draw, the alternator is working properly, and the battery is correct and not faulty, then there are no other reasonable ways to address this, besides what I have stated.

 

Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you.

Steve, BMW Expert
Category: BMW
Satisfied Customers: 23488
Experience: BMW Expert
Steve and other BMW Specialists are ready to help you

What Customers are Saying:

 
 
 
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
< Previous | Next >
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C.
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex
 
 
 

Meet The Experts:

 
 
 
  • Matt

    Matt

    Mechanical Engineer

    Satisfied Customers:

    92
    BEng hons Mech engineering, in auto industry 22 years
< Previous | Next >
  • http://ww2.justanswer.com/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Mechanical Engineer

    Satisfied Customers:

    92
    BEng hons Mech engineering, in auto industry 22 years
  • http://ww2.justanswer.com/uploads/Guest/2008-02-15_191551_avatar.jpg Roger's Avatar

    Roger

    BMW Master Tech

    Satisfied Customers:

    2823
    10 yrs. experience as BMW Master Technician, shop foreman and dealer.
  • http://ww2.justanswer.com/uploads/FO/fordtwo/2014-12-19_163422_arrepair.64x64.jpg Robert's Avatar

    Robert

    BMW Technician

    Satisfied Customers:

    82
    Fully qualified 19+yrs exp/self employed technician in the UK
  • http://ww2.justanswer.com/uploads/IN/indytech/2013-8-8_102717_SantoDomingo146598x6402.64x64.jpg Greg's Avatar

    Greg

    Technician

    Satisfied Customers:

    1089
    Automotive diagnostic tech
  • http://ww2.justanswer.com/uploads/TE/techmachine/0601821347169_717372168_8940977_39623330_o.64x64.jpg Ross's Avatar

    Ross

    Diagnostic and repair technician

    Satisfied Customers:

    467
    Licensed diagnostic and repair technician
  • http://ww2.justanswer.com/uploads/RO/RobMechanic/068.64x64.JPG Rob's Avatar

    Rob

    ASE Certified Technician

    Satisfied Customers:

    82
    30 years trade experience