2012 Toyota Prius Check hybrid system

Hello everyone, I just wanted a few opinions on an issue I am having with a used vehicle I just purchased. It is a 2011 Prius with the Check hybrid system error. It came on after 300-400 miles of the first week driving it. I thought it was the vent for the battery that was blocked due to the seatbelt so I removed the negative 12v battery post and drove it another 300-400 miles before it popped up again. I took it to the auto parts store and the codes they were able to pull were the ones below.
C1256 accumulator low pressure

C1259 hybrid vehicle control system regen

C1310 hybrid vehicle system

POA80 replace hybrid battery pack
What should my next steps be and has anyone experienced this before? I can start the car and drive it fine. The 12v read 12.8v the morning after we’re checking with a multimeter. The electric motor seemed to work fine when disconnected the battery and reconnecting but I just want to be safe. I’ve looked through many threads on here and none are similar enough to my issue to help me begin looking in a certain area. Any help is appreciated, thank you for your time.

 

Do you have any idea what the other codes could mean or would I have to take it to someone familiar with working on these cars? I just want to get a good idea of what I will need to spend to get this to a working condition again.

 

Thank you all for your advice. The car has 130,000 miles. No accident damage on the Carfax but that’s only reported accidents. The breaks seemed fine but I was comparing that to the 98 Camry that I had been driving. As for the fan I will Check that once I get off today. I figure it’s best to check all the cheap stuff and make sure all that works first before finally coming to terms with a new HV battery haha. You guys are a very active group of helpful people and I notice the same people typically respond to posted problems. Just wanted to say I appreciate all the advice/help being new to the Prius club.

 

Just a quick update. Took the car to the dealer and they said the hybrid battery is bad. $3500 to replace which definitely hurts but it is what it is. I was wondering if it’s fine to drive the car as is or if I should let it sit until I am able to replace the battery? Just don’t want to cause any further damage than what it has. Thank you guys again for your time.

 

I just got the news a few minutes ago so I’ll be picking the car and paperwork up a bit later. I’ll make sure to call around at other dealerships and to the Toyota corporate customer service as I’ve heard of people getting some discount on the battery. I looking into the DIY refurbished hybrid battery pack but the only concerning thing to me is I haven’t heard to many long term success stories. Difficult decision to make with that much money on the line but the Toyota battery seems like the safest bet. Just hoping I can get some kind of discount.

 

I definitely appreciate all the input from people with experience. I got all the paperwork that the Toyota dealership and it seemed less than helpful. Just had the POA80 code but also has all the stats included with the motor temp, inverter temp and voltage on battery. With this paperwork and looking at the voltage I can tell that there is a problem with the battery. I am in the same mindset that I don’t want to wait until stranded one day. The reason I wanted all codes though was to make sure I don’t dump thousands into it and find out I need extra parts. Pretty frustrating but I may try and Check some stuff out on my own. My main concerns are the fan for cooling, ECU as it seems that could cause issues and also the inverter itself because that seems pricey to replace.

 

If I was to replace these myself would it put off the inevitable? Would it be worth the time and money for the extra battery life you could get out of it until replacing the HV battery?