Announcement

Collapse
No announcement yet.

Yamaha P-95 piano powers up, no output.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Yamaha P-95 piano powers up, no output.

    Apparently this is a common problem with this keyboard, no sound from headphone jack or speakers. The service manual can be found, but does not include any schematics. A fellow at another sight figured out that by replacing electrolytic caps C216 and C217 on the AM board situated in the center of the bottom frame, that sound returned. Several other folks with the same problem followed his lead, and fixed their keyboard. I have one in with this exact problem, and replaced those two caps, with the same positive results. They are two radial 100uF/16v, I used 25v. Good information to archive here that might help someone as it did me, because no way would I have found this out on my own with no schematic. So hats off to the very smart fellow from Germany.

    I would add that if you attempt to get inside this keyboard, the first thing you must do is remove the small metal cover on the underside of the frame and release two fragile ribbon cables. You must do this before you can separate the top and bottom halves after you have removed about sixty screws.
    It's weird, because it WAS working fine.....

  • #2
    Had same problem with P-85 with same fix. Looks to be same AM board. Drove me nuts.
    Schematic in P85 service manual at Elecktrtanya.
    Has to do with protection circuit of the output IC. From what I recall, at power up it detects too low of a load resistance because of parallel path on headphone board through those leaky caps.
    The one I worked on could be tricked into working if it was powered up with headphone connected, or brought up slow on variac, or at less than full line voltage.
    Still have an extra output IC as it was the first thing I tried replacing (before I found schematic).
    Originally posted by Enzo
    I have a sign in my shop that says, "Never think up reasons not to check something."


    Comment


    • #3
      Many thanks for this! Still helping techs in 2021 ;-)

      Comment

      Working...
      X