Who can confirm: P0420 DTC display identifying upstream or downstream sensor as cause?

In another thread, discussing P0420 and whether it indicates a cat converter problem or an upstream or downstream sensor problem, and what workup steps are needed to tell the difference, this claim has been made:

"P0420 will give a description on Tech Stream what sensor or bank it is, signifying upper/lower etc."

The claim was doubled down here:

"Tech Stream literally gives the description and/or sub codes to tell the tech where to look and what the actual problem is."

When asked for more detail, the same poster said this:

"Bank 1 Sensor 1 Bank 2 Sensor 2 Lean/Rich It's not rocket science, it's a simple DTC with description."

I'm happy to let "Bank 2" slide as a typo (as the Prius has an inline-4 engine, there is only one cylinder bank, Bank 1), and just focus on whether someone can show Techstream displaying P0420 in a way that pinpoints one or the other sensor as the cause of the code.

When invited to offer a screenshot or the like, the same poster replied:

"There's always Google images that show this, if you're just generally interested."

So taking all that at face value, it sounds pretty easy to find such an image, no?

Not sure why it's not easy enough to just be supplied by the person making the claim. But I'm happy to ask if anybody else can show what it looks like for a P0420 report to pinpoint that the cause of the problem is one or the other sensor. That's something that would definitely be worth knowing, as it would save a lot of time/effort compared to the troubleshooting steps given in the repair manual, so it's hard to believe the one person making the above posts would be the only one around here to know about it. Somebody else must too, surely?

 

That's the same list of "trouble areas" you find in the repair manual for the gen 3 liftback—same place you find nine pages of troubleshooting steps you can use when you have a P0420 so you find out which of those things caused it.

But getting back to this thread, V Sport has claimed "Tech Stream literally gives the description and/or sub codes to tell the tech where to look and what the actual problem is."

That would sure be faster and easier than nine pages of troubleshooting steps, so if anyone can share the details of what to look for in a Techstream P0420 display to be literally given what the actual problem is, it would be great to get that info more widely known. Lots of PriusChatters, after all, do use Techstream.

Maybe a concrete example helps with the focus. If you see this shown in Techstream, does it tell you "where to look and what the actual problem is"? If so, what is the actual problem that produced this code?



Also, in a different case where the actual problem was one of the other possibilities, what would be the difference in this display that would tell you that?

 

@Datuna14, can you clarify why you wrote "p0420 b1s1" above? Did you actually see the code shown somewhere with s1 in the description? Can you describe where that was, what scantool or app or reference source presented it that way? Can you include a screenshot? Thanks!

 

The question here—the whole original question of this thread—is whether a P0420 code gives you specific "sensor 1" or "sensor 2" information. Notice there is no "S1", "S2", "sensor 1", or "sensor 2" shown here:



@Datuna14 posted about a P0420 code, but wrote "p0420 b1s1", so the clarification question was: why did @Datuna14 write "s1" there? Was @Datuna14 using a scan tool that somehow displayed a P0420 code with "s1" in the description, or looking at some online resource that had "s1" in the description? More info or a screenshot would help.