I'm not sure of the exact reason yet, but I have a drain on my battery to where if I don't drive at least once a week, I get the dreaded "click, click" sound and no start . A reading at the battery gets me 11.6 v... certainly not enough...

FWIW, when mortoring, I'm charging at 14.4 v or thereabouts, so that's not the issue...

So, while at Harbor Freight yesterday, I got their solar battery charger as it was 1/2 off, or only $9.99. It's doing its thing as I type, and I just wanted to share in case there are others who might want such an item...

http://www.harborfreight.com/cpi/cta...emnumber=44768

 

I have a similar unit that I ferry around into vehicles that sit around for a while at a time (like the MINI in the dead of winter). Problem with these plug-into-the-lighter-style of chargers for us is that the supplied sockets are disconnected from the battery when the key is off. The power from the solar charger will not reach the battery when the car is shut off and parked if you are using the console lighter socket. I have added a couple of constant-powered sockets to my car, this allows chargers such as this to work as well as let me leave things powered up independently of the car running (cell charger, laptop, power inverter, etc).

The MINI has a lot of electronics sitting in standby mode when parked, moreso than a lot of other cars IMO. A trickle charger like this should practically be standard equipment!

One thing is comforting is that despite all the high tech, if you have a manual trans and a battery that has just a bit of juice left, you can still push-start the car with no problems.

 

Is your battery original? If so, it's probably time to replace it. Unless you have added a lot of electronics that require constant 12V, the battery should not die within just 1 week. It could also be a bad alternator, but you've already checked the voltage when the car is running, so that's not the cause this time.

The solar panel is nothing more then a patch for the problem. Fix the problem at the source and the panel only becomes necessary for long term storage.

 

aDeLoreanGuy, I indeed plan to fix the problem, once I pinpoint it, as I alluded to in my first post by saying "yet." For 10 bucks this a nice safeguard to have in the interim. And as Greatbear mentioned, I too will make my MINI a seasonal ride, but for here in CA, it will be my Fall/Winter transportation. A RWD convert will be my Spring/Summer wheels...

So, this trickle charger will have a permanent purpose in the not-so-distant-future...

Due to fact that I added a couple gauges under my toggles (voltmeter & oil temp), along with a shift light, I have no access to my 12 supply anways. In my Euro parcel shelf, I added a dual cig lighter, non-switched . Also wired in the Parcel shelf are four billet aluminum, LED toggles: UNIChip A/B, driving lights, aux interior light, and sonic deer avoidance device. Oh, and the MINI aux input...

A photo of the then unfinished work under the toggles:



Just realized that I didn't answer your question! I ditched the BMW/MINI battery 2+ years ago. I now have a Braille, with the battery box removed, paving the way for a straight-shot, custom exhaust:

 

Oh, that makes since now. Dry cell racing batteries are notorious for loosing their charge over a short period of time. Combine that with the fact it only has 15 AH of capacity (normal car batteries are at least 40 AH), I'm not surprised it needs to be recharged every week.

I couldn't find any information regarding its internal resistance, otherwise I could figure out if the 1.5W solar panel is enough to compensate for the internal drain of the battery.

 

aDeLoreanGuy, unfortunately, it's not the battery per se... DrObnxs also has this same battery and he's gone much longer than a week w/o issue. I have a drain somewhere, and I'm not quite too sure where to begin... But I'll figure it out!

 

If you leave the key in the ignition, or even close to it, the battery will go dead in a couple of days.

(Take out the key, open the door, then bring the key near the ignition switch. The dinger will go off, just like you had left the keys in it.)

Saw this information on other posts from people who left the keys in the car when it was in the garage and the battery would go dead.


John

 

John, that's a new one for me! Really cool info to know. Thanks for sharing. As for me, that's not the culprit... Unless keeping my key in the house, yet 10' way is close enough...

 

Dang, while eating dinner, I started to remember when I wired the dual cig lighter... I didn't want it to charge my cell phone or iPod accidentally if left connected over an extended duration of time. And I just went-out to verify, and it is switched, by design. But that doesn't help me now...

Any recommendations on how best to modify this unit to go direct to the battery? Thanks much.

 

Get a voltmeter and some fuse taps. Take the key out, leave it in the kitchen and then look for a fused link that's live with the voltmeter. Voila!, you have the place to tap in.

If you need one, I have some extra fuse taps. I think they're a couple for a buck or so at Radio Shack (that is, until they stop selling components other than cell phones!). You can look at the PLX install thread for some photos. I used the fuses in the driver side kick panel....

Matt

 

Thank you Matt. After lookig at your PLX thread again, I see what you are referring to, and I do have a couple of those lying around. I also have a one or two of these Add-A-Circuits as an option:



However, with access to the battery being easy, I'm still thinking about going direct. Given where I park the MINI at home (as seen in a photo above), the sun's path would necessistate that I put the solar panel in the rear... which is where the battery is, on the MCS...

With that blue shirt material removed that covers my battery, this is what I have:

 

will help with wieght distribution!!!!

Whatever works for you, works for me. You can always use a connector for fast plug and go, or is that unplug and go?

Matt

 

I snipped-off the cigarette lighter portion of the charger and wired-in red and black alligator clips. These secure very nicely on each terminal's small threaded holes as seen looking downard in the photo above. I will cut two very small holes in that blue shirt so I can hook this up quickly...

Now I need to find what's sapping the battery! This set-up has bought me some time...

 

Just to share my experience, a Coleman 4W 12V solar battery charger via OBDII port worked, although the cig. lighter does not in my R56 2013 Mini Cooper JCW. I unhooked the battery and tested the leads to it from the cig. lighter and OBDII.