Service diagnostic mode.

I don,t know if you are serious but you don,t have to load it if it is 11.9 volt.
The computer of the Chr is clever enough to load the 12-volt battery if it is needed

Of course you dont. But you will be replacing your battery in 1-2 years if you dont. Ask the old prius owners about that one. If i was planning to drive I wouldnt have worried. The longer you leave it flat the faster the plates degrade.

Under 12 volts (under no load) is pretty much dead. I might pop a solar panel on the shelf.

By boost it I meant pop it in park and turn it on for 10 minutes.

http://www.energymatters.com.au/components/battery-voltage-discharge/

Success but to my knowledge, the 12-volt battery is loaded by the 201,6 V main batterij. But if you think that it help do it.

I have driven a 2010 Auris for 6.5 years.
I drive short stretches on 4 days a week.

I found no problems with the 12v battery or the traction battery.

The 12v battery is only used for onboard electronics.
And as Holyhead said, it is recharged via the traction battery. The traction battery is protected via electronics to prevent depletion.

My traction battery was very low when I parked. Maybe this left it unable to maintain itself. I also do short journies but also dont drive for 3 days sometimes. Thats a long time to leave a 12v battery at 25 percent.

In its defence all my other cars needed a solar panel to stay above 12.4v and my civic almost lost the door key codes when it went flat. For the sake of a little 5w panel id rather not get stranded like the previous owner did. They had to get a tow to honda to recode the system.

Dont forget I had also watched a film in the car left in neutral recently. Im not sure if it charges the 12v battery in this mode. Il have to check.

I didnt come here to bash the 12v system just give you an easy way to view it among other things.

How about we all go into the hidden menu and post our voltages after the car has been sat overnight. Might be more interesting or useful.

I leave my car for 3 weeks when on holiday or away for work. Never had any problems.

You should leave the car turned on and in park when using the power outlet for an extended period of time.