Battery Question(s)

[foghat]

Hey all,

I need to double check the paper work, but I am quite sure my 2008 is on the original battery. I imagine at this point it is living on borrowed time. That said, I have had no battery related issues at all - save the clock resetting this winter after I hadn't used the car for a couple of weeks.

Question is: when the battery is on the way out will I get any warnings/messaging? Or will the thing just crap out and leave me high and dry?

If there are warning lights, I will probably wait for those. If not, I will probably think about preemptively replacing it over the summer.

On that note, has anyone tried using one of these for the registration:

http://www.autoenginuity.com/product.../bmw-sr01.html

Thanks.

[bmw1racer]

^ Good questions.

It'd be nice to know if there are any clear indication that the battery is on its last legs.

[JimD]

It depends on how the battery fails. If it develops an internal short or open circuit, there will be no warning it will just not work and will refuse to take a charge. I think of that as happening mostly on relativly new batteries but that is almost certainly not absolute.

The chemical process of a lead acid battery is not completely reversable. Gradually sulfer builds up on the electrodes and the battery doesn't charge up as well and discharges more quickly. That is a gradual process. Generally there will be a slow crank or other indication before the car just doesn't start. Even then it can be jumped or charged and will function.

I don't replace batteries as a preventative measure. I generally have multiple vehicles at the house and jumper cables, however. So if one car doesn't work, I can jump it or switch cars. I also have a couple battery chargers. If I was totally dependant on one vehicle, I might think more seriously about a preventative battery replacement. But sometimes batteries last a really long time and some new batteries fail right away. My boat battery is over 15 years old. I have a deep cycle for the trolling motor, however, that could start the outboard if I needed it to. I had to replace a new battery in my daughters car once. It had a hole in it and a cell without acid.

[Dackelone]

I believe for Canadian cars, you guys had a Battery recall. IF it was never done BMW owes you a new battery. Check with your local dealer. The recall was only for Canadian market cars. I think BMW puts a higher cold cranking amp battery in.

[1ToBeOn2Wheels]

I'm still on my original 2008 battery; no issues or signs it's on its way out. I have heard that strange electronic gremlins can occur when the battery is near the end of its lifespan.

[foghat]

Originally Posted by Dackelone

I believe for Canadian cars, you guys had a Battery recall. IF it was never done BMW owes you a new battery. Check with your local dealer. The recall was only for Canadian market cars. I think BMW puts a higher cold cranking amp battery in.

I will talk to my SA about that and also double check my paperwork. I don't suppose you have a linky to said recall do you? My search results are cluttered the the battery cable recall.

[MZWIE]

Jumper cables baby. Frankly, there is really no way to tell. The day it fails I will buy a new one.

[BBursey]

Originally Posted by foghat

I will talk to my SA about that and also double check my paperwork. I don't suppose you have a linky to said recall do you? My search results are cluttered the the battery cable recall.

Hey.

I probably have the recall letter for the battery somewhere at home; I can check tonight and post it. It was Canada-wide and replaced the original 70 Amp-hour battery with a larger 90 Amp-hour battery.

Cheers,
Bryan

[NorthernDancer]

First, I would buy the Innova Equus 3721 battery monitor. Its only about US$18 from Amazon, likely other sources too.
Second, buy a Battery Tender, CTEK or Schumacher battery maintainer and use it whenever car will not be used for a few days in cold winter. Maybe also on those super cold nights.
From what you say, I'd say you have 1 or 2 more years in your battery if you occasionally use a battery maintainer.

[Dackelone]

Originally Posted by foghat

I will talk to my SA about that and also double check my paperwork. I don't suppose you have a linky to said recall do you? My search results are cluttered the the battery cable recall.

Sorry, I do not have the Canadian battery recall pdf. (IF anyone has it please send it to me!)...

I believe that the recall is if you have a 70Ah battery they will switch it to a 90Ah. Hope this helps.

Btw... I asked my German dealer how much the AGM battery costs. They told me a little bit over 200 euros. I also asked how much to code and install... they said they would do it for 40 euros. I was shocked at such a low price after reading the battery horror stories on 1Addicts.

[PA135i]

I was told by my SA that one symptom would be the clock will have trouble keeping time. Dash related problems. I am on my original also and will give it one more year.

[foghat]

Originally Posted by BBursey

Hey.

I probably have the recall letter for the battery somewhere at home; I can check tonight and post it. It was Canada-wide and replaced the original 70 Amp-hour battery with a larger 90 Amp-hour battery.

Cheers,
Bryan

That would be great. It would seem I have a 90 amp battery, but do not have it being replaced in my records. I will check with my SA tomorrow. if it was done under recall, that may explain why it still seems to be working like a top.

[mleskovar]

Originally Posted by NorthernDancer

.....Innova Equus 3721 battery monitor. ..

Thanks for the tip.....just bought one. Will save me from hooking up the DVM to check charge level.

[foghat]

Originally Posted by NorthernDancer

First, I would buy the Innova Equus 3721 battery monitor. Its only about US$18 from Amazon, likely other sources too.
Second, buy a Battery Tender, CTEK or Schumacher battery maintainer and use it whenever car will not be used for a few days in cold winter. Maybe also on those super cold nights.
From what you say, I'd say you have 1 or 2 more years in your battery if you occasionally use a battery maintainer.

Thanks for the info. Will look into it.

[foghat]

Originally Posted by Dackelone

Btw... I asked my German dealer how much the AGM battery costs. They told me a little bit over 200 euros. I also asked how much to code and install... they said they would do it for 40 euros. I was shocked at such a low price after reading the battery horror stories on 1Addicts.

SA quoted me $538 cad for 90ah 900a agm. Installed and coded. $411 for the plain jane 90ah.

[JimD]

Originally Posted by foghat

SA quoted me $538 cad for 90ah 900a agm. Installed and coded. $411 for the plain jane 90ah.

My dealer was advertising $175 installed. I didn't need a battery so I didn't investigate. It probably was not a AGM but I don't think we really need that.

I looked at that battery tester. It is a voltmeter in a convenient package. That's OK but you can do the same thing with a regular multimeter (if you have one). The only extra features are that it plugs into the accessory outlet (aka cigarette lighter outlet) and has lights to help you understand the results. You have to know low voltage with engine not running = battery not doing so good AND low voltage with engine running = charging circuit not doing so good (so battery might be OK if it got charged properly). But for less than $15, a little added convience could be worth the price.

[PA135i]

SA quoted me $417 installed. $175 is incredible.

[MightyMouseTech]

Originally Posted by e34m5

Jumper cables baby. Frankly, there is really no way to tell. The day it fails I will buy a new one.

Any modern battery tester will tell you the capacity of the battery compared to new. When we test a battery it will give a result like (Battery at 80% charge, 74% capacity).

[RoundelM3]

The battery on my wife's 2011 128i failed a few months ago - just like that! Drove home from work in the evening, and it was flat as West Texas the next morning. Would not even jump start. BMW towed it in and replaced the battery at no charge, and the car now runs even better than it did before, leading me to think the original battery was defective. Failing 3 years after delivery is unusual - the one on my 2007 E92 lasted 5 years. As so many components in the engine are dependent on the electrical system, it's strange that a low-current condition didn't get picked up during routine maintenance/scans, etc.

[MZWIE]

Originally Posted by MightyMouseTech

Any modern battery tester will tell you the capacity of the battery compared to new. When we test a battery it will give a result like (Battery at 80% charge, 74% capacity).

True. But that is not a harninger of impending failure. It is simply an instantaneous measurement.

[New21er]

5 year old battery = time to replace.

[JimD]

There is another type of battery tester and it isn't terribly expensive. You can get a CCA reading if you check the voltage under load. Harbor Freight sells a tester that will do this and it's pretty cheap, I think I paid about $20 but that was a sale price. It is also a voltmeter with a special scale but includes a heavy duty resister and a momentary switch. You hook it to the battery with cables and then push the momentary switch for a few seconds to get a reading. The same tester will tell you if the alternator is working (my measuring voltage with the engine is running) and other things.

To check the only thing you can sensibly check, sulferization of the battery, I like my little HF tester. But batteries can outright fail, as documented here, and I don't know how you test for that. A load tester might find something before outright failure occurs but only if you test a lot. I doubt anybody would.

It is also possible to check for a continuous load when the car is off. You need a high (like 10A) ampmeter. I bought one at Walmart when my daughters car was not starting after it sat a few days. It was pretty cheap too, like about $25. You pull the negative battery terminal and put the meter in series with the battery with the car off. Current should be in the low milli amp range. Hers is about .25 amp. I narrowed it down to a circuit (by pulling fuses) but havn't found the issue.

Here's a link to the local dealers pricing:

http://www.bmwofcolumbia.com/battery-service.htm