PDA

View Full Version : Battery going dead @ 2 months?


RickR
07-08-2005, 09:07 AM
I have a 2005 M3 that I took delivery of on May 20th. Production date was October 2004 and looks like the dealer took delivery around the end of December 2004.

Sorry to say I have not had a chance to drive the car that much the last three weeks (only 500 miles after about 2 months). When I went out to the car to crank it over last week, the battery was too weak to do so, so I had to put it on an overnight charger.

About a week later, I got the BMW trickle charger from Pacific BMW (arrived yesterday) and plugged it into the cigarette lighter. After 16 hours it is still showing that it is charging the battery.....

What do you all think? A bad battery that cannot hold a charge, or something that is pulling current from the battery? Can I check the current draw with an ammeter? What is normal inactive current draw on this car? I have a convertible with NAV, Harmon Kardon, cold weather package, PDC, Xenon, and the ice>link iPod adapter that I added.

This reminds me of when I had BMW batteries go dead over time in my 633csi....is it possible that the dealer did not keep it charged for the 5 months that it was on their lot? Or is there something staying on that I cannot see?

Your suggestions are welcomed.

spta97
07-08-2005, 10:05 AM
I had the same problem with my old Maxima that I only drove 4000 miles in two years. The issue with batteries is if they sit idle for too long they loose the ability to hold a charge. You can probably get it to start up the first couple of times, but after a while the battery needs to be replaced. I would imagine that this is a warantee item (although my Nissan dealership would only "pro-rate" it).

I ended up going through two OEM batteries then I purchased a Sears Die Hard Gold and a trickle charger and did not have the problem again. I was warned though that having a car sit for too long is not a good idea at all and you should take it out for at least 12 miles a week to keep things lubricated and moving.

FlyingDutchMan
07-08-2005, 10:26 PM
Yes...replace the stock battery with a Optima. I used to work for Cutter Motors in Santa Barbara and bad batteries on new cars is really common.

Once you have an Optima you'll but them in all your cars. I can leave the parking lights on over night and the car still starts, and they last years.

Pinecone
07-09-2005, 04:40 AM
My battery died at 2.5 months.

spta97
07-10-2005, 08:34 PM
Yes...replace the stock battery with a Optima. I used to work for Cutter Motors in Santa Barbara and bad batteries on new cars is really common.

Once you have an Optima you'll but them in all your cars. I can leave the parking lights on over night and the car still starts, and they last years.

I tried the optima before getting the die hard but the terminals did not line up properly and the cables would not stretch. Do they fit the M3? Also, I assume you are talking about the yellow top?

Pinecone
07-13-2005, 10:59 PM
You need an Orange top (which is no longer) or 34R (the R means the terminals are reversed from normal).

spta97
07-14-2005, 05:22 AM
Do the terminals fit for the M3? Mine should be here in a month and I've been told this is a worthy upgrade (especially if you are running an after market stereo).

bren
07-14-2005, 06:58 AM
I assume you are talking about the yellow top?
Yellow top is deep cycle....unless you plan on running the batter down quite often get a Red top.

spta97
07-14-2005, 07:11 AM
Yellow top is deep cycle....unless you plan on running the batter down quite often get a Red top.


I was reading up on them last year and the red top was better for starting power but the yellow top was preferred by stereo enthusiasts. It seems that the deep cycle was better for large bass notes. Another advantage is that it is a dry battery and can be mounted in any position (not really a concern for me).

I will be running about 1000 watts RMS when I install my system - not a ton but if I could stop the diming lights without the use of a capicitor I via use of the yellow top I would. They are not cheap though - about $165 - $185.