Yellow warning triangle with key not detected message

I have a 2012 Prius 3 with 270,000 miles. I use my Prius to help me through power outages, in this case caused by hurricane Helene. I connect an inverter to the 12 volt battery and turn the car on. It recharges the high voltage battery for about two minutes every twenty minutes. Last year it kept my fridge and freezer running for 3+ days. I am doing it again. I keep the power draw down to around 300 watts or less. I changed the battery in the key fob. The voltage on the new battery was 3.3v. When I start the car, there are no warning lights, but after a minute or so, the yellow triangle comes on along with the “key not detected” message. I do not know if the message and the yellow triangle warning light are connected. I have the Dr. Prius app and it says,”no ECU error codes found”. Any thoughts on the situation? Thanks in advance for the help…

 

Thanks Tombukt2 for the input. The red light helped solve my problem. I am embarrassed to say that I put the battery in upside down. That fixed the issue. Both the yellow warning triangle and the message went away.

 

It was not working with the old battery. The voltage was 3.0 volts. Apparently that is not enough. The new battery is 3.3 volts and it works.