Battery Problem?

[JimD]

This seems all over now but does anybody know if a hygrometer will work on recent BMW batteries? Back when batteries used to have caps over the cells that were easily accessable, when I had a concern about a battery I used a hygrometer, a simple device with balls in it that you draw a little battery acid into to test, on each cell. If you have a cell that is weak, you know in a few minutes at minimal to no cost. I still have one of these in a toolbox somewhere. They at least used to be a couple dollars at an autoparts store. Modern batteries make it hard to get the caps off but I have done it before and if you can get the cap off, and there is battery acid available to draw up into the device, you can test it. The the mat type electrode, however, I'm not sure there is free battery acid available to test. Anybody try this? When batteries go bad, there will be a cell that is very weak while the others are still fine. The six cells seldom all get weak. This incident seems like a case where a cell failed prematurely. Occasional use made things worse but I don't think it was the entire cause. Mine gets used only occasionally, often sitting multiple days, and it is fine.

Jim

[NorthernDancer]

I use my 128 rarely; battery voltage drops to about 12.4 volts. An unused battery will start to loose power thru sulfation. Most of the new modern chargers have circuitry to counter act sulfation. I charge my battery usually once a week when not being used and/or for a few hours before being used.
Now that you have BMW charger, use it about once a week if car not being driven and you'll be fine.

[eogintz]

Thank you Noithern Dancer.

I plan to use the charger once a week and probably more often once it gets really cold outside. I do use the car every day but just for a couple of short trips which I guess is not enough to keep battery fully charged. I think that the charger routine and new battery will work out.

P.S. I have read that 5 and 7 series are also having similar problems with battery drain. In fact, my SA at dealership said that at least the 1 series gives you advance notice of a problem with battery which in my case was the clock losing it's memory. He also said that if my car was a 5 or 7 series I would have not been able to start the car and been stranded. Strange?

I also read that some Mercedes models are using two batteries and still having problems with battery drain. My wife drives an Infiniti M35 and my son has a G35. Both of these cars have all of the electronic features that my 128 has yet they have never experienced any kind of battery failure. Neither one of them drive very much. I wonder how Infiniti manages power use without having any problems with batteries and why can't the Germans copy their systems?

Thanks again,

Ed

[Dackelone]

Originally Posted by eogintz

P.S. I have read that 5 and 7 series are also having similar problems with battery drain. In fact, my SA at dealership said that at least the 1 series gives you advance notice of a problem with battery which in my case was the clock losing it's memory. He also said that if my car was a 5 or 7 series I would have not been able to start the car and been stranded. Strange?

BMW has always had battery problems due to all the electronics they put in the cars. Even way back in the e34 and e38 days... they had prolems when the cars sat for a week or two.

On those cars (e34 and e38's) you could not even unlock the car! The door lock cylinder was electronic and it was a real PIA to unlock when the battery was dead. Basically you had to pump the door lock cylinder and slowly the door lock know would rise. Then you could open the car. Then came the hassle of jump starting and/or blowing up a ECU/DME. Most people don't realize German cars use a brown wire for the negative and a black wire/cable for the plus. At least many tow truck drivers did not.

[eogintz]

Hi Folks,

It has been a week and a half since BMW replaced my battery and performed diagnostics on the car. I have had no problems with starting or losing clock memory etc... Still not driving very much since I am retired and other than errands around the neighborhood I have nowhere to go. I do use my car everyday but not for long distances.

As you recall it was advised by BMW SA to buy the BMW Advanced Charging System and to use it. I figured that since battery was new I had some time before I needed to put the charger on car.

Yesterday morning I plugged it into car as per written instructions that came with it and got solid red signal on charger for quite a long time.

After many hours (maybe like 10) it changed to flashing green (means battery 80% charged) and by this morning I had solid green signal on charger which according to instructions means battery was fully charged. I then disconnected it from car.

I was surprised that it took 18 hours on the charger to get a solid green signal since battery was installed only a week and a half ago. I thought that I did something wrong but I guess that battery from dealership was not fully charged when they installed it and this charger charges pretty slowly. I guess it is set up this way so that the slow "trickle" charge does not damage battery or other electronics.

This was the first time that I have used one of these chargers and at least now I know that it works. It was very simple to use but a bit disturbing that I will probably need to use this once a week on a new battery.

For those of you who are planning to use this charger just be prepared to have your car charging for almost a day ( I guess longer or shorter depending on condition of battery.) Don't get discouraged like I did that you did something wrong since it takes so long to charge.

Ed

[JHZR2]

This is totally expected. Those deltran chargers are 1.25A. The battery is somewhere from 70-90Ah. So just think how many hours it will take to put in, say, 20A, which would be around 25% depleted.

Of critical importance is the temperature compensation which the better battery tender and battery minder models have.

Like cooking ribs, low and slow is better. Makes it easier to recombine the gases produced during charging and prevents dryout.

[mleskovar]

Originally Posted by JHZR2

This is totally expected. Those deltran chargers are 1.25A. ....

Yes, that's par for the course with a 'trickle charger'. They are not designed to charge a flat battery. I've been told that using any type of charger on a "smart charge" system is a no no. Like when you put in a new battery the system has to be "normalized" to accept it. I think it's bs but I'm no expert. Does anyone know the truth? I can't imagine a trickle charger being a problem and I can't imagine a battery replacement requiring a diagnostic intervention to "accept" it and make it work properly.

[Boosted_N54]

when I plugged in my cobb v3 it shows my 135i battery voltage at 13-14v is this good

[PA135i]

My radio randomly shuts off sometimes ... then comes back on. Is this a sign that the battery is going?