Preserving settings while disconnecting the battery

[Lewis&Clark]

So tomorrow I'm going to do a persistent power mod, so I can keep my electronics charging even while the engine is off.

I'm curious though. I hate disconnecting the battery. I know, it's pretty trivial all things considered, but having to reinitialize the windows, re-enter all the radio and GPS settings, address books, etc. is an annoyance. I'll live with it it needed, of course. BUT... I stumbled across the item below and wonder if it's actually doable.

Powerbuilt 648539 Computer Memory Keeper


My understanding is that the head unit and onboard computer of most cars only need a very small amount of power flowing in order to preserve their memory. Nevertheless, it surprises me that, ostensibly, one only needs to connect a simple 9 volt battery to supply enough power to keep the memory in tact.

Anyone done this?


dt

 

[tucktuck8]

I recently disconnected my battery to install my HID's and when I hooked everything back up my radio stations were all saved... I had to reset the auto window, sunroof, and back window but it saved my radio stations. I don't know how but it did..

 

[Adumb]

These are from Autozone

I think this is the one they normally stock

 

[Lewis&Clark]

These are from Autozone

I think this is the one they normally stock

So these things actually work?

 

[Adumb]

So these things actually work?

I don't have any experience with them. I think the $12 one i posted needs to be plugged into an external power source.

 

[Sungod]

So these things actually work?

Of course they work, but (and this should be your concern is that if you have to disconnect your battery for anything other than a battery replacement) you are doing so to protect your electronics. If you use a product to keep power to those devices, you are defeating the purpose of disconnecting the battery.