This Grand Caravan was working fine until this morning.

I put some gas, and turned on AC for about 20 mins.

Suddenly its dashboard started to blink 'no Fuse' message.

I couldn't turn off the car for 10 mins. The message changed into 'no Bus'. It blinked for another 10 mins. I could see the red battery warning icon. Now, the dashboard is permanently turned off and I can't start my car anymore.

It doesn't respond to my key fob. Does this mean that I should replace its battery?

Please help

 

Get the battery checked.

 

Wow! I found out why.

The car has several modes. Yesterday, I didn't fully start the car. I put the car in 'Start/On' mode that solely runs on its battery. I used AC in that mode for 20-30 mins.
That totally killed the battery.
A mechanic recharged the battery and the car is working again now. He advised me to fully turn on the car when using AC.

Thanks for your advice.