I've got a Yamaha P95 piano that is not working properly. When I power it on in test mode, it should emit a continuous tone. Instead, the tone starts continuous but quickly turns into 5 or 6 short beeping tones, then silence for a bit. Then this sequence keeps repeating. I've attached an audio file of the problem. Does anyone have advice on how to diagnose what might be going on? I'm a noob in electronics but can find my way around a digital multimeter and can solder and de-solder ....

the P95 uses the P85 service manual ... https://forum.allaboutcircuits.com/attachments/p85schematics-pdf.248453/ with additional updates ... https://elektrotanya.com/yamaha_p95b_p95s.pdf/download.html

 

DOH ... problem solved ... the owner brought me the piano and power supply and I assumed it was the correct power supply without checking it! The supply he brought was 24 vDC and the piano requires 12 VOLTS! Plug in a 12 volt power supply and it works fine!