Expert: Cleggsan - 10/5/2008

Question
Pioneer xr-p770f (yes I know its old) System will accept cd but does not recognize it.  I took sides off to see inside.  The disc isn't spinning either.  It grabs disc but the display reads "no" regardless of which space (1-25) I load disc into. Any suggestions besides using it for the radio and tape deck only?

Answer
First thing to try is a hard reset: Unplug the power cord on the unit for 30 minutes, then power it up again.

If that does not help, please read on.

Since the disc is not spinning it must be determined why that is so.

Actually, it may spin just a nudge or almost imperceptively and you didn't notice it.  This very first reading is to verify the TOC or Table of Contents on the disc which is the first thing the machine looks at. If there is no evidence of a TOC it will stop the search.  

So, there are several possibilities that, probably, only a trained tech can test and troubleshoot for.

ONE:  The servo mechanism is not working and has lost ability to drive the spindle or drive motor on the disc platform.  It is mostly a problem with an IC.

TWO:  The laser beam is too weak and does not get a reflected beam back which is strong enough to be detected.

THREE:  The focus and tracking systems if way out of adjustment due to wear or being badly bumped and knocked out or alignment.

FOUR:  The optical tracking system electronic feedback system and error correction system is malfunctioning.

It being an old player you may want to weigh the cost of repairs vs the cost of a replacement unit. And, there may be some difficulty in obtaining parts for such an old player.  New multi-disc cd players are now around $99 and up.  Repairs at a shop may be more than that.

Hope this helps.

C