when the password is lost, the standard official method is to perform a . Note that this process erases the internal load memory of the CPU , meaning the existing program and data will be lost. Steps to Unlock via Factory Reset Prepare a Memory Card : Use a Siemens SIMATIC Memory Card (2MB or larger).
: Insert the prepared "empty" card into the PLC and turn the power back on.
Observe the LEDs: The (Maintenance) LED should blink, indicating the reset is in progress.
: Insert an empty, formatted Siemens Memory Card into your PC.