The window from the Maintenance > Battery> Set date and Time. "Change Battery" has popped up on my car touch screen about 10 times today. Does my 2007 Lexus RX400H have 2 batteries and if so, which one would the message be referring to?

 

The 12 volt battery under the hood more than likely. Have it checked at some auto parts store. Out here in Az it is hard for mine to last 3 years.

 

That is just a countdown timer that was set years ago. It may not have been reset the last time the 12 volt battery was replaced in the past.

 

Oh yea, forgot that is in the program, might very well be that instead of the actual battery having an issue...

 

@smassey321 and @weighit, thank you for your replies. I will have it looked at.

 

if you want to wait --and live on the edge!-- you can wait for the shifter to display warnings like' must be in park to start'. i found out,inadvertently, that my shifter problem was directly related to my 12v battery. changed battery and haven't had message or starting problem since(touch wood!).

 

Please, be aware that it is not a regular 12V battery. It is a deep cycle 12V battery. It can be replaced with any DC battery, as far as it fits the cables and compartment layout. I have seen some very decently priced ones that run about $100 plus.OEM Panasonic is ridiculously expensive. Many, self included, did Yellowtop Optima.
You have thermistor and gas vent to take care of. I do not believe gas vent is absolutely crucial to have but... I rigged my Optima so that its flat vents were connected to venting hose. Thermistor is simply gently pried off the old battery and moved to a new one.
As I am wishing you well, and after many posts on 12V replacement at TN, pretty please, have back up power connected to battery cables during replacement. It may save you a lot of headache down the road.
If you replaced it and goof lights came up all over the instrument cluster, do 3 consecutive complete power cycles - ON/OFF. This is recommended by Toyota. If it didn't help - it's dealer from that on.

 

i didn't know this. i have searched and read the manual and nowhere does it mention deep cycle. i hope you are mistaken as i've just recently put in a 'normal' 12v battery.the car parts store recommended my 12v but did not mention anything about deep cycle , even though they sell them. where did you get this info?thanks.