As many of you know, many Yamaha receivers (including the RX-V1, RX-V800, RX-V1000, RX-V2000 and RX-V3000) have what are called EXTENDED IR CODES, which is an unbelievably extensive set of discrete codes! And included in these is a DIAGNOSTICS TOGGLE which pops up a connected video screen that looks very "dangerous" for non-technical users, including as many as 12 parameters that can be entered or changed (or messed up!).

I did a complete forum search for YAMAHA DIAGNOSTIC and found only this thread...
[Link: remotecentral.com]
which is very informative, but also makes reference to the mysterious nature of that function.

So the question is: Does anyone here know what the DIAGNOSTICS MODE does and how to use it for YAMAHA receivers?

BTW, THANKS to Barry and Rob and the many others who have taken the time to work all of this out for us other Yamaha receiver owners! Here are some other threads related to YAMAHA EXTENDED IR CODES in case your curiosity is piqued...

[Link: remotecentral.com]

[Link: remotecentral.com]

Doug,
The "Diagnostics Mode" was publicly posted by mistake. I'm assuming you found the "Diag.Mode" Extended IR Code on the Yamaha website or from a tech or someone affiliated with Yamaha. It has no end-user value and is designed to be used by service personnel.
Aside from this I'm sure you can atest that Yamaha has one of the most flexible receiver lineups out.

George, thanks for the response. I had already suspected that those codes were probably "not for public consumption" due to their nature. I have deleted that button from my ccf. Actually, most people who might eventually encounter that code, though, probably have enough technical savy to understand and take care. But thanks again for the feedback. And you are right: we "PRONTOITES" should give a giant round of applause to Yamaha for 1) putting out such a great line of receivers, and 2) including such an amazing array of discrete codes, and 3) being so user-friendly as to share them with us!!!!! As you may have noticed from other threads here some manufacturers have no interest in the user beyond the sale. So THANKS YAMAHA !!!!!!! (And my local Yamaha dealer has been terrific in support, too.) Anyone who is considering what kind of new receiver to buy (as I did for almost a year) would be very happy choosing one of these new Yamahas: I am! I came close to buying a Denon, which is a wonderful piece, too, but the great flexibility of the Yamaha swung me over.

Doug (add 2002 to my name in email address)