I would like to use a "memory keeper" device when I change the battery on my 2002 ES300. I see from a Toyota forum that the typical 9V memory keeper that fits into the cigarette lighter socket doesn't work for Toyotas and Lexuses. Has anyone had experience with memory-saving devices on their Lexus? Thanks- Richard W.

 

Nine volts would seem too little. However, you could get one of those booster packs(12v) that plug into the cigarette lighter and that would keep the system voltage up when the battery is disconnected. The computer and radio should have no way of telling that the battery is gone.

 

This one works on Lexus Gx470, should works on ES300.

 

I have use this memory saving 9v battery that you could get from walmart and it did not work for me. So i just return it back. Don't know why it didn't work maybe the 9v is not enough to save the memory.

 

Are the power points in this car powered when the car is off? I don't think they are, which would explain why the setting saver doesn't work, when the ignition switch is off, the powerpoint has been removed from the circuit, i.e. "off" so plugging in a battery to that circuit to backfeed power would not work!