I REALLY need some help here

A few days ago, our 2004 Prius cut out on my wife mid-drive. After having it towed to our house, I proceeded to try to figure out what was wrong with it. I couldn't for the life of me get it into ready mode and I got the transmission lock abnormal message, so I had a feeling it was the battery, which was further solidified whenever the lights start going dim. Sure enough I take the old battery out, and it has a dead cell. I bought a new battery put it in and now the lights and everything working fine, but it still won't go into ready mode. Thinking it was the brake switch, I went and got one, and replaced it as well. Still no ready mode. When the car cut off on her, she had a good bit of gas in the car, but whenever I turn it on, the display is flashing at one bar. It's not saying that the transmission lock is abnormal anymore, but whenever I turn it on, it displays the word problem, but does not elaborate any further. I ran diagnostic mode to check the battery, and it says it's pulling 11.9v. I assume that's good? I'm at a loss here, I feel like I've tried everything. Does anybody have any ideas? I also want to add that we had the large battery replaced last year. So I don't feel like that's the problem.

 

I think I've got it fixed now. I feel like the battery was the problem, considering that the old battery had a dead cell when I got it checked. After putting a new one in, it threw me way off that the car didn't start. After reading around I decided to remove the service plug for about 10 minutes then plug it back in. Now the car is starting, no problem. Besides the usual problems, like the dash display not coming up. But that's normal. And from what I've heard, that's normal with a lot Prius owners. I have had a red exclamation point ever since I was overdue for an oil change, and it didn't go away after the oil change, but I've had a lot of cars that have done that, due to the stuff needing to be reset. When I get the chance, I will run it through a code reader, just to be sure.

 

Nevermind, that exclamation point was from when the major battery was going dead, before I had to Shell out a ridiculous amount of money to replace it.