AC fault codes

Hey, Prius owners! I'm new to the group. I was troubleshooting the AC system with the neat feature by holding the ac auto and recycle buttons on the steering wheel and presing power on twice. I get code 43 and that's it. What does code 43 mean?I looked everywhere online and there is no one that tells you. When I bought the car I didnt find an owner's manual. I do know that it leaks refrigerant. I am refilling every month or sometime more often than that with the correct refrigerant.