I have a 2004 RX with the original Panansonic battery and decided it's probably a good idea to replace a 8 year old battery as preventive maintenance. I bought a Fit 3 battery from Costco recommended by a member on this forum. Anyway, the question is can I use a battery charger to connect to battery terminal during battery removal/installation to save all my settings? Thanks in advance.

 

Ya know,thats a good question. I would think you could,but never personally tried it. Something about this idea scares me though.

 

The idea scares me too. In theory it should work but hate to short something while attempting it.

 

I have never done this but I have used a portable jump starter plugged into the power outlet and than turned on the ignition before removing the battery. This worked fine for me I just slid the battery terminals inside a good leather glove to keep it from shorting out on any thing. Not sure if the charger would be any different, if you do it make sure you are careful to cover up the leads to keep them from shorting against any thing.

 

...have to ask...what's dealer procedure?

 

The answer is 'yes'. I did that (though with a 'compact booster') when I changed the battery of my BMW. You - obviously - have to be careful not to short any of the cables. It works very well and maintains all your settings.

 

Update: I didn't use the battery charger as I originally intended to. Instead I used a jumper cable like the above ^ person suggested to connect from 1 of my vehicle to the Lexus battery terminate cables. The Lexus terminate cables are very short so you'll need an extra pair of hands. One carefully holding cables while the other remove and install the battery. I retained most of my settings beside the clock which reset to 1:00 clock and the temperature which reset to 75. On a side note the fitman 3 battery from Costco is about an inch shorter in length compared to the original Panasonic battery. Don't know if that matters or not.

 

Maybe it's just me, but is it really such a big deal to reset :

1. Power windows
2. Power sunroof
3. Memory seats (nothing to reset, you seat will be in the same spot, just set your seat button to remember the spot)
4. Radio presets

If you have a 2006 400h, you'll also have to reset the ISC.

 

I regret that you lost some settings, though I wonder why that occurred if you had connected the jumper cable before disconnecting the Lexus cables from the battery you were changing....