Re: [DML] electronic challange for all

[Martin Gutkowski <webmaster@xxxx>]

Hi Hank

The simplest way is exactly as you describe - get one hefty diode and 
connect the stereo's main power feed up via it. You can then wire up an 
auxiliary 12v pack feeding the stereo UPSTREAM of the diode. As soon as 
the main battery/alternator outputs 0.7v more than the aux pack, it will 
be topped up, but the diode will prevent the aux pack leaking out to the 
rest of the car's systems..

The disadvantage is that you are using a doide in a fairly high current 
application. Just make sure it's not thermally insulated, and spend a 
few $$ on a decent one, and I'm sure it'll be fine.

I would suggest a small sealed lead acid cell from a manufacturer like 
Yuasa, or alternatively you could go all high-tech and buy a 12v NiMH or 
NiCad Sub-C pack from www.battlepacks.com

As to the phantom current drain, have you tried unplugging the main 
harness to the lock module (if you have a stock one) - even if the main 
red wire is disconnected, the module can still draw current if some of 
its components are dying.

Martin
#1458 & #4427

Hank Eskin wrote:

> I have a Sears "Security" Die-hard battery which shut itself off if its
> voltage drops below a certain level (around 10 volts), in order to preserve
> enough juice to start the car when I return (in case of the low current
> drain many of us experience). It's a great feature - I only drive my car
> once a week or so, and the battery is always charged enough to start the car
> once I reset it with the key-fob remote.
>
> I also have a new Alpine radio. As you can suspect, each and every time the
> batter turns itself off, I lose all the settings and presets, and there are
> alot of them on this head unit.