2010 Prius codes c1310 and c1259

are you sure the 12v battery is not low?

 

Not really, but I can see how a game of 'telephone' could end up there. These codes represent the communication of an error.

I made this image for another thread, glomming together bits of different pages in the manual. Never mind the P0A80, we don't know that's your code yet. But look at the detection conditions for C1310 and C1259.



Notice that each one requires that "communication with power management control ECU is valid". (Emphasis mine.) So it is not a communication error, it is straight up valid communication with the PMC ECU, and the PMC ECU sent actual messages to the brake ECU saying "hey, I'm having some internal issues affecting regen, you're going to be on your own for slowing the car down" and the brake ECU sets those two codes to confirm it received those messages.

The key is going to be to find out what code(s) the PMC ECU has, which will be the reason it sent those messages. If what you're using to read codes is only showing you those two in the brake ECU and not the code(s) in the power management control ECU, you're going to need something better to read codes.

Once you know what the power management control ECU is actually complaining about, it will probably be a quick step from there to what's needed to make it happy.

 

Try resetting by pushing start button on and off 3 times without pressing brake

 

I think you picked a great car to start. Pretty much every manufacturer has at least one hybrid car.
I would double check every connection, carefully. And make sure the 12v battery IS good.
What is the voltage of the battery?

 

I wouldn’t say it’s too ambitious. Aside from the special hazards of the hybrid system, diagnosis and repair of Prius cars is similar to working on other modern, computer-controlled vehicles: you can’t rely on the traditional methods of the shade-tree mechanic, nor on message-board postings and videos, which may or may not have complete or reliable information.

Fundamental automotive knowledge and mechanical aptitude are still important, but to work safely and efficiently, technicians also have to be able to use the diagnostic and repair information and tools provided by the manufacturer. In particular, you need access to the edition of the Repair Manual (more info) that covers your car, and, for many problems, a Toyota Techstream diagnostic system (or equivalent) that can communicate with all of the car’s computers. Neither of these is necessarily expensive.

Toyota’s technical training materials, available by subscription to techinfo.toyota.com, are also worth reading; see especially course T071, Toyota Hybrid Systems, but many of the others are equally relevant. Unlike the Repair Manual, New Car Features, and Electrical Wiring Diagram, most of the training materials are offered as PDF documents, which you can download to read later.

 

If it were me, I wouldn't really bother trying to make up some catch-all concept like "resetting the hybrid system". I would just ask the power management control ECU what it wants to tell me, look in the repair manual for what to make of whatever it told me, and then take care of whatever the issue is. It can often be something quite minor and easy, but guessing at it or trial and error will not always be the quickest way to the destination.

I agree with others here that don't see that as much of a problem. As Elektroingenieur's response also suggested, working on modern cars, there is a lot of information you get by asking the car. If anything, typically 17 year old kids tend to be more accustomed to asking computers stuff than we old timers are. Suggestions you read from us dinosaurs will often sound like a lot of "try this thing, try that, check that, it might be the so and so", as if we've either never realized we could ask the car, or we're just somehow determined to show we can solve the problem without it no matter how much extra work we're making.

You do have to be careful what you do with what the car tells you. You can't assume that it's telling you exactly what the cause of the problem is or exactly what you need to do about it. That's a mistake some novices make, but the car's computers are stuck in boxes and can only tell you exactly what they saw; they can't climb out, poke around, and find out why they saw it. Usually the human has to do some of that.

In particular, avoid reading too much (reading much of anything, really) into the one-liner "fortune cookie" that you might encounter when looking up a diagnostic code. It is better to go straight to that code's section in the repair manual and look up exactly what that code tells you the computer saw. It's your job to figure out why it saw that. Usually the same section in the manual will go on for several more pages of carefully targeted things you can check so that you get the answer as directly as possible.

 

When you connect a laptop with Techstream, you just make one connection to the OBD port under the dash, and Techstream will use it to talk to all two dozen computers in the car. But Techstream knows a thing or two about how to do that, which some other code readers may not. There are in fact a few different networks in the car, there are gateways to hop through to talk to some things, etc. Techstream knows the nitty-gritty topology details.