Hello,

On a S7-300 CPU314 (314-1AG13-0AB0), I can't put my PLC online or load anything inside of it (see the screenshot). Does anyone know how to solve that ?

Hi,

perform the memory reset as requsested in the error message.

How do you reset a SIMATIC S7-300 CPU and MMC (default reset or overall reset)?

You can try this first:

MMC
It is only possible to reset the MMC if it contains data^*that is invalid for the CPU. Otherwise the MMC is only initialized by the procedure described.

All the user data is deleted when you reset the SIMATIC Micro Memory Card (MMC). Proceed as follows.

1. The MMC is slotted in the bay of the CPU. The CPU requests an overall reset (slow blinking of the STOP LED).
2. Set the switch to "MRES" and hold it there until the STOP LED lights continuously (approx. 9 seconds).
3. Within the next 3 seconds, you must let the switch go and set it again to "MRES". The STOP LED now blinks during the delete procedure.

If the CPU continues to request an overall reset after the procedure described above, then the MMC is defective.

regards

sancruz

Thanks, it was my MMC that was defective.

Have a good day

Regards,

T. Schenker