Hi: Well, the Mini is in storage for the winter. I have a BMW battery tender plugged into the cigarette lighter for battery maintenance. My question is, the car has been plugged into to battery tender for over three weeks, and the charger is still flashing red - indicating still charging. (the BMW battery tender will display a solid green light when fully charged and in tender mode) I had read that the BMW battery tender that plugs into the cigarette lighter will work in a 2009 Mini. Is that not accurate? The battery should have been topped off by now........... Thoughts? Thanks ! John
Are you sure your lighter socket has power with the ignition off? My 2011 335 sockets are dead without the ignition on so I can't use them. Connect directly to the battery. A little inconvenient, but guaranteed to work!
You need to install the pig tail directly to your battery. If you leave just enough of it showing to put the tender on it. It will work then.
As others have stated before me, the socket is dead (disconnected) when the ignition is off. Use the supplied pigtail set-up and connect directly to the battery. Battery Tenders really do work well. I use them on my motorcycles. For example, I have one on my (purchased October 2002) 2003 H/D FLSTS, and it still has the original battery.
Ok, thanks for all the replies. Looks like I need to connect the battery tender directly to the battery - will do. Thanks again, John
Direct connection to the battery did it. The battery tender topped off the battery over the weekend. I was sort of surprised how quickly it topped off - considering the car hadn't been started for about a month .... I am guessing the parasitic drain from the electronics in a Mini is far less than the resting drain from the electronics in my 550i. John
I have a battery tender hooked up to my stored 335 via the terminals under the hood, and it topped the battery up within a few days. I have heard a lot about the BMW charging system being able to read the amount of charge the battery can take based on it's age and life left into it. There seems to be a difference of opinion on whether or not to "register" a replaced battery due to this variable charge capability. My question is this: Does the battery tender bring the battery back to it's fully charged capacity above what the computer has been charging the battery too? Or can an aging battery only go back to its current level of charge? Maybe this is a dumb question, if so, sorry!
No, its not a dumb question at all. And, the answer is... it depends on the battery tender. The answer should be found in your battery tender's documentation, as every one I have ever owned has included a brief explanation of its charging characteristics. The tender is going to follow ITS programming on battery charging, not the car's program.
