Originally Posted by raid
My M9 got a new sensor less than 3 years ago. I sent the camera to NJ Leica, and they installed a new sensor. This sensor is now corroded according to Leica NJ. So the "new sensor" from last replacement is not from the "new sensor" generation? Maybe.
Raid it depends how much less than three years:
The "new" sensor was announced in June 2015 and around October that year they began fitting them.
The new sensor required updated firmware which was the early "tell tale", there have been updates since so that ID has gone, new firmware adjusts for either sensor.
It is possible to look at the hidden data in the M9 service menu AT YOUR OWN RISK:
Delete -> up (2x) -> down (4x) -> left (3x) -> right (3x) -> Info
Cleared by turning the camera off.
Under Hardware you should see something like:
CCD ID 15, CCD Board 2, Control BRD 2, M16CID 0.
The CCD ID of new sensors is 15 and 16 (thought to be the year but not proven) 5 and 8 and 11 are old sensors, the MM has a different code. All anecdotal and unconfirmed by Leica but owners have dates returned and data accessed, this despite the sometimes vague Leica paperwork which often does not clearly state what was done.