Raspberry camera error: "mmal: No data received from sensor" -

i used raspberry camera times ago. tried again acquire image raspistill -o image.jpg command; red led on camera flashes, error:

mmal: no data received sensor.  check connections, including sunny 1 on camera board

of course camera connections fine. there other way check if camera still working?

this error appears because of faulty connection camera. had exact same problem in different camera+pi configurations. following case encountered:

the connector not correctly inserted either in camera or in pi.
the sunny connector (the small yellow 1 on camera) not connected well. (now gets interesting)
if remove , reinsert camera in pi please sure remove power pi. sensor sensitive , spark on wrong pin burn it. (i did unfortunately) trigger problem pi connector pins. confirmed pi2 connector may have bad soldering lead cold contact soldering. can fix using flux on pins , pass soldering iron hot end on pins remake connection.
i used longer cable had both connectors on same side of cable. if connect can burn sensor , pi not start because of power surge (also camera gets hot in case). not remove pi without removing power before. cable have remove blue plastic 1 end , bend connector contacts on other side. insert end in camera since not removed/inserted pi end.

Overvie