Brake Override Malfunction. Car won't start.

After a couple of days parked I got the following error in my Prius C 2015:

"Brake Override Malfunction"

Now the car won't start. I doesn't even respond to the keyless door lock. If I remember correctly, it also said to contact the dealership.

It also made a weird continuing noise, the likes it alwas does when turned off. Kinda like a suctioning vacuum.

Isn't there a correct sequence to start ? eg. press the brake and push the start button. I might of not pressed the brake this time. IDK.

Could the computer be reset ? Any ideas ? Thanks.

 

UPATE: I had a hunch the auxiliary battery was discharged. I removed it and now it's charging externally. Will update.

 

UPDATE: I removed the 12v battery and after around 11 hours of external charge ( using DieHard 71219 6/12V Shelf Smart Battery Charger and 2A Maintainer ) the car started normally and drove around the block without error messages.

IMO The culprit was the lack of use for about 3-4 days and a voltage drain from a small QYT KT-8900 ham radio I had installed. I read somewhere, if I remember correctly, those radios draw around 20 milliamps when turned off.

I disconnected that sob.

I will soon consider (1 year max) replacing this 12 v battery anyway to prevent any future surprises.