Battery Life While Parked

[mackeroni]

Originally Posted by CivicDuty

If you have comfort access the water will lock and unlock your car as it passes over the handle.

I noticed this not only on my E82 but my wife's Honda that also has comfort access.

I put my key back in the house when I wash it at home and that does the trick.

Am I reading you correctly? Are you saying that the water from the car wash locks and unlocks your car? Does this mean that I can spray water on the door handle of a parked car that has comfort access to unlock it? Sounds like a serious security risk.

Peace... Mack

[mackeroni]

Originally Posted by JimD

I do not use a battery tender. My battery is about 10 years old and still working fine. Until a little over a year ago, I did not drive my car daily, I drove it 2-3 times a week. It sometimes sat for over a week, usually in my garage. If a car sits for a month or more, I think it is wise to charge the battery. But I would not do it daily. I see no benefit.

I read through the link and I think it is an interesting read. It doesn't directly address coding for the battery but I think it helps to explain why the car "needs" coding. It also doesn't seem to address trickle charging the battery. If the "intelligent" charging doesn't sense you are doing this, it seems like it would not be a good thing. It could lead to over charging of the battery. But probably not by much.

I would not put much faith in the 3 per cent savings comment. That must be under very unusual conditions. The alternator is a significant drag on the motor when it is putting out a lot of energy. But it is still a small amount of what the motor is supplying, most of the energy goes into moving the car. This system doesn't radically reduce the energy the alternator provides, it changes it a small percentage. A small percentage of a small percentage has a hard time getting the 3%. But I think it's a good thing. Using the "free" energy of the coasting car is a good idea. Reduces brake wear a tiny amount too. I'm not as much a fan of leaving the battery a little undercharged so you can charge it when coasting but considering how long my battery has lasted, it can't be a terribly bad thing.

Yes, it is easy to understand why coding the battery to the car is necessary in order for Intelligent Alternator Control (IGR) to work properly. My confusion, now that I have a better understanding of how IGR works, is about the good or bad effect that I exert when I apply a battery tender to raise the charge of the battery that my car is purposely trying to keep below full charge so that it is in a charge-receptive state when I am driving. IGR may not know that I am trickle charging my battery, but the operation of the IGR in Low, Medium and High modes while driving is dependent on the state of charge of the battery which is easy for IGR to determine.

Wish there was an easier way to say this. I feel as if I am poised to be dropped into the crackpot chute.

Peace... Mack

[CivicDuty]

Originally Posted by mackeroni

Am I reading you correctly? Are you saying that the water from the car wash locks and unlocks your car? Does this mean that I can spray water on the door handle of a parked car that has comfort access to unlock it? Sounds like a serious security risk.

Peace... Mack

Dude....just like your hand can lock and unlock a comfort access car, water does the same. But you need THE KEY CLOSE ENOUGH to do so. That's why walking around your car with it in your pocket is flashing your lights.

So does that mean you can walk up to any car with comfort access, touch the handle and open the door? No, of course not!

[JimD]

I guess that full charge only requires the car measure the voltage of the battery. So it should know. Then if it responds to that input by not trying to charge further, putting the car on the tender only "wastes" the energy when you are coasting. I don't see that as a big deal.

My theory on cars, however, is to fix things that don't work (at least if I really need them to work) and to change the fluids periodically to minimize wear. I haven't replaced my 10 year old battery, for instance, because it still works and because I've batteries in other cars only last a couple years. A new one might not be much better than what I have. For the same sort of reason, I don't trickle charge a battery just in case it might need charging. If it needs it, it gets it. But if it's working, I leave it alone. I will replace a belt or a hose if it starts cracking or something but generally I leave things alone as long as seems reasonably possible.

[gjm120]

A little promo for using battery maintainers - when I first got my car it gave a battery discharge warning from me playing around with the idrive and stereo to learn how it all worked. Soon after that I bought a battery charger/maintainer (CTEK) and put it on whenever the car was going to sit for 2-3 days or more. That battery lasted 2 1/2 years more without a problem until it just died one day.

[Matticus91]

Originally Posted by mackeroni

Am I reading you correctly? Are you saying that the water from the car wash locks and unlocks your car? Does this mean that I can spray water on the door handle of a parked car that has comfort access to unlock it? Sounds like a serious security risk.

Peace... Mack

Originally Posted by CivicDuty

Dude....just like your hand can lock and unlock a comfort access car, water does the same. But you need THE KEY CLOSE ENOUGH to do so. That's why walking around your car with it in your pocket is flashing your lights.

So does that mean you can walk up to any car with comfort access, touch the handle and open the door? No, of course not!

Yes this happens every time I wash the car, not a concern unless you're right next to the car.

[mackeroni]

Originally Posted by JimD

...I haven't replaced my 10 year old battery, for instance, because it still works and because I've batteries in other cars only last a couple years. A new one might not be much better than what I have. For the same sort of reason, I don't trickle charge a battery just in case it might need charging. If it needs it, it gets it. But if it's working, I leave it alone. ...

So you don't routinely put your battery on a maintainer and it has lasted over 10 years?

Originally Posted by gjm120

A little promo for using battery maintainers - when I first got my car it gave a battery discharge warning from me playing around with the idrive and stereo to learn how it all worked. Soon after that I bought a battery charger/maintainer (CTEK) and put it on whenever the car was going to sit for 2-3 days or more. That battery lasted 2 1/2 years more without a problem until it just died one day.

So you did routinely put your battery on a maintainer and it lasted about 5 years?

The conclusion from this small sample is that our batteries might not have to be kept at full charge to live longer. Maybe the IGR recharging process which keeps the battery in a charge-receptive state actually helps to extend battery life. Hmmm.

Peace... Mack

[bmw1racer]

Originally Posted by mackeroni

The conclusion from this small sample is that our batteries might not have to be kept at full charge to live longer. Maybe the IGR recharging process which keeps the battery in a charge-receptive state actually helps to extend battery life. Hmmm.

I suppose with all of the electronics in today's cars, battery life is shortened.

I had my E36 for 18 years and only replaced the battery once. And that was only because I thought I had gone way too long without replacing the battery.

[JimD]

Yes, my car will be 10 in June so my battery has to already be about there and I have never charged it or used a maintainer. Most of it's life it was driven one day during the week and on weekends. Sometimes it sat for a week or more. It has always started up fine. As long as it continues to do so, I plan to keep doing what I'm doing.

But my commute is 30 miles each way so the battery gets a chance to get charged up often. If my driving was different (and it will be before too long when I retire) I might need to charge more often.

[Tenspeed]

I put my car on a battery tender a couple of winters ago when I noticed it cranking slower after sitting for sometimes weeks without being started. It always starts strongly since I have been keeping it charged.

Putting the tender on it has become a habit during the winter months when I don't see myself driving it in less than a week because I want my battery to last as long as possible.