december 2016.
In vehicles built in 2001 under my project management and where several small software changes have been done in the last years, replacing the CPU of the PLC lead to a vehicle that did no longer work properly. Investigation showed that a hidden parameter in the setup, entered by the manufacturer of these vehicles, prevented it from stepping through subroutines. The software has been changed to work around this and no longer requiring subroutine functionality. A number of these vehicles have been sold in Africa and these showed the same problem after being without power-supply for longer time.
at all points