We have a unit of MC9S08JM60 which after several months in the field, appears to have had the contents of its Flash memory cleared. When we examined the contents of Flash memory via HCS08 Flash Programmer, we see that memory at all locations is 00, so program data has somehow been erased (or overwritten since erasing results in FF?).
There is no possibility of the MCU being reprogrammed out in the field so we are investigating how this might have happened. I would appreciate any ideas or details of similar experiences. Thank you.