My camera encountered a fall and I have the message after pressing the shutter “Camera error. Turn off power and On”. But that never helps! Removing the battery clears the message but the problem still exists. Is it because of damaged shutter ?
Assuming it happens with a known good lens (or no lens at all):
The shutter is about the only essential moving part in an a6000 - there is no mirror, no aperture actuator, no AF motor, no IBIS (there is a sensor cleaning mechanism with an ultrasonic actuator, though). It would be a likely candidate.
Sony FAQs say that this message indicates either a shutter, lens or IBIS problem. A6000 has no IBIS. A lens problem can easily be isolated by not attaching a lens.
Other things that could have taken damage and indirectly cause such a malfunction:
A switch or dial could have gotten knocked into making contact in a pattern that is impossible when intact
External contacts could have gotten bent and shorted together (hotshoe, card socket, or lens mount)
Some metal enclosure part could have got bent enough to short something electrical out
Some flex cable got knocked out of its socket
Some heavy electronic component (eg an inductor or electrolytic capacitor) got sheared or broken off a PCB (unlikely that an a6000 enclosure would survive that kind of impact intact).