Not sure if the 2003 is the same as the 2000 I used to have, but changing
the battery on the 2000 did not clear any nav info.  You did, however, have
to re-enter the security codes on both the radio and the nav and you lost
the radio presets.

On 1/25/08 12:35 PM, in article
2bac38aa-f038-45b2-9080-8354c933c166@v46g2000hsv.googlegroups.com, "ventura"
<robert.w.scheffel@gmail.com> wrote:

I can't speak to the navigation system but I've always been able to keep my
radio stations by hooking a 9V battery across the battery leads.  The 9V
battery keeps the radio memory alive.  I've done it three or four times with
no ill effects.

------------------------

_If_ you use the 'cigarette lighter' port, you have the key turned to
the Accessory position (or is it position II?), since that one is dead
when car is shut off.

'Curly'

Changing the battery will not reset non-volitile memory in the unit but you
will need the security code if it has one.

I can't be sure about the navigation system but I have been successful
in changing the battery in a number of cars without losing any data,
settings etc. by doing this:  I connect a 12DC volt power supply to the
battery cable terminals--when the cables are removed from the battery,
12 volts DC is still powering the system and nothing is lost.

Ken

Is it an OEM navi system - i.e., it came with the car originally? I
would have to believe that there is some sort of short-term memory
built in, kind of like a Palm, that allows you a period of time
without power without dumping all the data. Your owner's manual may
say.

Dan D
'07 Ody EX
Central NJ USA

Thanks for all the suggestions. I'll try the ones involving a second
12v battery, either connected directly or through the power port.

To answer the questions -- this is the factory installed navigation
system and unfortunately doesn't have a memory protect feature like a
Palm. The owner's manual says that any addresses entered by the user
will be erased when the battery is disconnected, so the 2003 model
must work differently from the 2000 model.

I don't mind entering a security code to reactivate the radio and
navigation system after changing the battery (hopefully this has
reduced thefts of these items), but losing 50 or 60 addresses is a bit
much. Honda needs to rethink this one! Switching to non-volatile
memory (like most cell phones) seems like the best solution.

Update ---

I was successful in doing this by plugging a 12 volt battery into the
power port.

Thanks again to everyone for your suggestions.