Glad I found this forum , hello to everyone! I’ve had many cars since I was 18 (Nissan 240fx, Escalade , jeep wrangler, BMW 328is, Benz 320 SEL, and a couple more) and have to say this used 2014 Prius C I purchased 7 years ago has been the most dependable and non problematic car I’ve even owned! unfortunately I’m at 110K miles and the dreaded check hybrid system message popped up on my screen. I did disconnect the 12v battery and hybrid / orange switch for 15 minutes and it did disappear however Im sure that’s just temporary. Currently everything is working fine and it seems I’m actually getting a bit better mileage. here’s a screenshot of the reading I did , does it look problematic ? Thanks for any help!
Is this the car's 2nd or 3rd 12v battery? These cars have notoriously small aux batteries. Just a stab in the dark. Priussys are the most dependable of the breed and it's a shame that they didn't make the cut - but that's been the fate for just about all subcompact hatches. The market (and the OEMs) want CUVs which have bigger everything - especially profit margins. Good Luck!
Hello! I believe it’s this cars second. I installed a new one on May 23rd, 2024 so I’m thinking it’s probably still good?
Make sure you keep the battery intake cooling vent clear. Behind the drivers seat, below the rear seat bench. Maybe clean-out and test that cooling fan assembly. I know mine use to run hot while driving through the Sierras. So hot that I could feel the heat radiating off, below the rear bench seat.
Right thanks for that , I clear it out once a month due to my husky’s fur! Checked again , disassembled it and all is clear (did a cloth cleaning for extra measure)
Well, the hybrid batteries in the c model tend to last "about ten years" which means you're right on schedule for a replacement. The 12v batteries tend to go 4-6 years, so I'd think one that was new in 2024 still has a ways to go. The built-in diagnostics are pretty good, but they aren't perfect. I'd say there's a strong chance you do need a new hybrid battery, but you should very definitely confirm this either by taking it in to a pro, or tooling up to DIY.
Ya now I’m not sure yet , I’m going to research and see if I can DIY as I’m pretty good with doing that given exact directions.
Another member with a 2014 Prius C here. My very orange 2014 Prius C still had the original 12V battery until I replaced it last year in November(2025), and I'm not sure it would have been dead if not for a month I didn't drive it because it was on a Cargo vessel. I didn't even know there were built in diagnostics. I just went straight to buying an OBD2 scanner compatible with Dr Prius software. Specifically a "NexLINK Bluetooth OBD2". OP - you may consider getting one? There might be cheaper ones out there but that was the cheapest I could find that I knew would work based on what the Dr. Prius website said.
When I refer to built-in diagnostics, I'm referring to the OBD system. Even though it is crude in the sense that it just tosses up the message "Check hybrid system," it tends to be pretty darn accurate. When the root diagnostic code is found to be P0A80, it is right most of the time. 3rd party software like Dr. Prius is pretty good for getting details about the hybrid battery, but it doesn't do much more than that. We (speaking for a certain group of Priuschatters) have found the Autel AP200 to be the least expensive comprehensive scanner; capable of interacting with every system on the entire car.
