How do I reset factory settings on Yamaha p155

Question edited for clarity.

Try a Factory Reset. Try a power reset first. Disconnect from the mains plug for 15 minutes.

System Reset - Yamaha PSR-S750 Service Manual

ManualsLib https://www.manualslib.com > ... > Service manual
There are two reset methods in the SYSTEM RESET display: Factory Reset and Custom Reset. ... This function lets you restore the status of the instrument to the ...

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  Yamaha PSR-S750 Reference Manual - System Reset

  https://www.manualslib.com > ... > Reference manual
  This function lets you restore the status of the instrument to the original factory settings. ... buttons to enter or remove the checkmark. ... operation for all ...
  
  

To reinitialize the IS-SPX-1000 unit to its factory default settings:
1.
Unplug the unit from the power.
2.
Push the reset button and keep it pressed.
3.
Power up the IS-SPX-1000 unit.
4.
Wait with the reset button pressed for at least 8 seconds.
5.
Release the reset button.
6.
The IS-SPX-1000 unit will now boot in the factory default mode.v

It's possible to reset the DTXPRESS electronic drum kit to its factory default settings by performing a Factory Reset. Here's how you can do it:

Press and hold the [DRUM KIT] and [SAMPLE] buttons while turning on the power switch.
The display will show "FACTORY RESET OK?"
Press the [DRUM KIT] button to execute the factory reset.
The display will show "INITIALIZING" while the reset is being performed.
When the reset is complete, the display will show "COMPLETED".
Note: Performing a factory reset will delete all user kits, samples, and other custom settings that you have made. Be sure to save any custom kits or settings that you want to keep before performing the reset.

You can normally reset Yamaha keyboards by holding down the highest note while turning on. If you want to do a full factory reset see below - remember this may delete all songs etc you have saved to the keyboard memory.

Turn off the p155 power.
Press & hold down the rightmost key (C7) while turning on the power. Once the power is On release the C7 key. It should reinitialize to the original factory setting

Double check the supply... it should be a PA301 which is 16 volt DC at 3.5 amps... fairly hefty one.

Download these schematics:

http://elektrotanya.com/yamaha_psr-1500_3000_sm.pdf/download.html

and

http://elektrotanya.com/yamaha_p-120_s.pdf/download.html

A lot of Yamaha have similar circuits between different models.

When you go to these links, scroll down the page looking for a small link "Get Manual". They will only let you download two a day without registering.

The first of these has the power entry on page 154... the second is on page 60. Both use the 16 volt power adapter. See if one of these schematics is not close enough to your unit to troubleshoot it.

Here is a link to the manual if you don't have one:http://www.dtxperience.com/documents/Manuals/DTXPRESS_IV/DTXPRESS_IV_Owners_Manual.pdf The procedure is on page 35.

When push comes to shove, a factory reset never hurts.

Assuming you'd like to proceed with a factory reset, follow these steps:

This procedure makes it possible to restore the S08 to the original factory-installed Internal Voices, Multis and System settings.

WARNING: The current settings for all Multis and User Voices will be deleted. If the current settings and data are not expendable, create a backup before executing the Factory Reset.

1) Press the [UTILITY] button.

2) Press the [JOB] button. The 'FactorySet' screen will be displayed.

3) Press the [ENTER] button. The 'Sure?' message prompt will appear.

4) Press the [INC/YES] button to execute the Factory Reset. The 'Completed!' message will be displayed to indicate the procedure has been successfully executed.

5) Press the [EXIT] button to return to the Utility Mode.

These are sold online at Kraft Music

Yamaha WB53080R Music Rest
Replacement Music Rest for P120, P140, P155, PF500, PF1000