Yamaha psr 400 give an Er 1 message when switched on and gives no sound when played. The demo works however

Not sure I was clear that I meant that ANY switch button or key was activated as power came on. This could either be a mechanically stuck button or key OR one that had an electrical defect... (it happens)



The firmware in these OFTEN scans the switches and keys during power on to insure that alll are in the unpressed state as a part of the power-on-test like is done on our PC's. ( You know that if you hold down a key onyour computer keyboard it fusses during bootup)



There is usually a special key sequence that is held down while power is turned on to do a factory reset of these units. SO they verify the switches are all normal while looking for the special reset sequence and would flag an error.



IF you happen to find a plastic button slightly sticking, use a bit of CRC226 to lube it. This is available in the electrical dept at Home Depot. Not sure I was clear that I meant that ANY switch button or key was activated as power came on. This could either be a mechanically stuck button or key OR one that had an electrical defect... (it happens)

The firmware in these OFTEN scans the switches and keys during power on to insure that alll are in the unpressed state as a part of the power-on-test like is done on our PC's. ( You know that if you hold down a key onyour computer keyboard it fusses during bootup)

There is usually a special key sequence that is held down while power is turned on to do a factory reset of these units. SO they verify the switches are all normal while looking for the special reset sequence and would flag an error.

IF you happen to find a plastic button slightly sticking, use a bit of CRC226 to lube it. This is available in the electrical dept at Home Depot.