Complete List of Toyota OBD2 Parameter IDs

I don’t know of a comprehensive, public source for this information. Toyota’s Repair Manual series (more info), for example, explains all of the diagnostic trouble codes and, in the Data List/Active Test topics for each system, lists the measurement items by name, but without PIDs or similar information; it’s assumed that the reader is using a Toyota Techstream (Global Techstream) diagnostic system.

At least in some regions, information needed to create third-party diagnostic tools may be available under license from Toyota for a fee. I imagine much of it could also be found by reverse engineering the Techstream software, either directly or by examining its CAN bus communication with the vehicle.

 

I was online renewing my local library card that I never use anymore and I decided to see what they had for repair manuals... Turns out they had every manual made for Gen2 Prius. Currently have the Bentley manual checked out for a few weeks...

But for a 2010 Prius, someone posted a PDF of you codes. Here it is:

 

No addresses, PIDs, or formulas in there though; if you had an OBD-II app that you wanted to teach to retrieve Prius operating data and somebody else hadn't already reverse-engineered PIDs for you to use (as has been done for a lot of the Gen 3 PIDs, there's a spreadsheet you should be able to hunt up), that PDF wouldn't help you.

 

Yeah... But that's a 112 page document of all known diagnostic trouble codes...
The more you understand the canonical assembly of those, the more you'll be able to focus your work on sniffing the right PIDs and reverse engineering how specific things are operating.

 

If I remember right, the protocol messages for retrieving DTCs are separate from the ones used to query data by PID. The Repair Manual has a number of sections detailing the data parameters you'll be able to see (if you're using software that knows the PIDs for them, like Techstream), but (as Elektroingenieur mentioned) doesn't actually tell you what you'd need to query them yourself. But a bunch of the reverse engineering has been done; there is a spreadsheet floating around here somewhere with Gen 3 PIDs for a lot of the measurement items, but I don't think all of them. That would be a handy place to start, to avoid duplication of effort.