Error D0C8: 'Block status' aborted becouse of inconsistencies between test job and running program

Hy all,

A customers' mechanic was troubleshooting a problem with one of their systems.

When monitoring a function (FC) only half of the block would be updated with the online information. Also in the status bar at the bottom of the editor he could see the following (printscreen in attachment):

(D0C8) 'Block status' aborted because of inconsistencies between test job and running program.

When he reloaded the block the original problem seemed to be solved and the monitoring was working again, so it seems that not all of the code was (correctly) executing.

Now I can’t find any information on this error online, so I was hoping someone here could give some insight to identify the cause and prevent such behavior in the future.

Here is some information about the system:
CPU: 414-2DP (6ES7 414-2XG02-0AB0)
This is a pretty old CPU so maybe it is hardware related and we should recommend replacement?
It kind of looks like some kind of corruption to me.

The mentioned FC is a pretty simple, combination of ladder logic and STL, no jumps, not even any block calls. Furthermore it is only called once in the program.

There have been some code changes to the system recently, but not to the part the mentioned FC controls. The last change to the FC was in 2010.

Hello,

I recommend as soon as possible save diagnostic buffer from CPU to file. Then you can check from date and time some events, also that for which technician was called. As technician have reload some blocks??? inside CPU hard to recommend what exactly was problem, check diagnostic buffer. You can also upload it here and say clear info about some date and time where we can look probably.

Dear Duris_I,

I did immediately look in the diagnostic buffer after the incident, but there were no new record's around the time the incident occurred.

All the entry's in the diagnostic buffer are distributed I/0 faults or restart information. They all happened during planned maintenances or changes, so noting out of the ordinary here.

Edit: The incident happened today (15-5-2018), the last entry in the buffer was on 05/12/2018.