Codes C1256 and C1365?

Hi, I have a quick question. Recently I just got a new hybrid battery as my old one was failing. I am still showing codes for low accumulator pressure: C1256 and acc pressure sensor c1365. I got my accumulator replaced about 6 months ago with a brand-new OEM part from Toyota. Last week I had a high-pitched beep and all the warning lights pop on, hard braking. Long story short I took it to Jiffy Lube and they did a hard reset of codes and let me know about the battery concern. Got this replaced which was very costly. So, my question is, since I'm assuming I still have both, those codes related to the accumulator and pressure sensor, however car is driving okay (will note that when running the A/C it's draining battery fast and air is not very cold). My thought is to call up Toyota where I purchased the part and they have a 36-month warranty. I want to avoid paying a 250 diagnostic fee as I had the guys at jiffy with top quality scanners already give me the codes. I want to get it either replaced or fixed, whatever is easiest to solve the problem and then get that sensor replaced. Do you know how I can avoid paying a diagnostic fee or since it's a warranty part I need to go to Toyota and just suck it up lol. Keep in mind I've invested over 5k into this vehicle in actuators, water pumps, new hybrid battery, and basic maintenance like spark plugs and coil packs. I am trying to save as much money as possible so please let me know what you suggest I do. Thank you