Yes, I know - it is a very old printer, but I want to make it print
again.
It just beeps 6 times while turning on, what means: replace printhead.
And I bought brand new black printhead (I don't use colors)
and it beeps again. I think, it's something like printhead sensor
error,
but I don't know where is the sensor and what can I do to fix it.
This is not the "waste ink tank full" error, the orange light is not
blinking.
Please, maybe someone knows this damn printer and can help me.
Thanks

This error is a defective print head error. You need to have both
print heads in the printer to work. So you options could be that the
black ph that you just replaced is defective, your colour ph is not
functioning properly or the printer PCB reading the ph is shorting out.